A solid composite electrolyte poly(PEGDA-co-AN)/ LiTFSI/nano SiO2 with high conductivity and high entropy structure and its Li+ transport behavior

A solid composite electrolyte poly(PEGDA-co-AN)/ LiTFSI/nano SiO2 with high conductivity and high entropy structure and its Li+ transport behavior | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A solid composite electrolyte poly(PEGDA-co-AN)/ LiTFSI/nano SiO 2 with high conductivity and high entropy structure and its Li + transport behavior Yafei Zhang, Xiao Wu, Shunjin Peng This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4682986/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 15 Oct, 2024 Read the published version in Polymer Bulletin → Version 1 posted 7 You are reading this latest preprint version Abstract Using solid electrolytes instead of traditional liquid electrolytes to assemble all solid state batteries can effectively solve the problem of electrolyte leakage and reduce risks caused by lithium dendrite growth during charging and discharging processes, which is capable to improving the safety of lithium battery. Solid polymer electrolytes have been widely studied in consideration of the factors, such as flexible structural design, convenient preparation, low cost, good interface contact with electrodes, and ease of large-scale production. Polyethylene oxide (PEO) polymers have a good salvation for most lithium salts, but PEO segments in polymers have high crystallinity at room temperature and a narrow Electrochemical Stability Window (ESW), which will limit some advanced electrode materials with high potential used in batteries and restricts the improvement of battery performance as well. Polyacrylonitrile (PAN) with high dielectric constant has high electrochemical and thermal stability, good mechanical processing properties, and excellent fire retardancy. In this manuscript, a cross-linked copolymer, poly (PEGDA-co-AN) is prepared using Polyethylene glycol diacrylate (PEGDA) and Acrylonitrile (AN) as monomers and 2,2-Azobisisobutyronitrile (AIBN) as a thermal initiator; the influence of Lewis acid-base interaction between nano SiO 2 additive and -C≡N or C-O-C on Li + transport has been investigated, and a new idea was proposed to improve the lithium ion transport in poly (PEGDA-co-AN) based polymer composite electrolytes by adjusting the local charge environment of polymer electrolytes. Finally, a composite polymer electrolyte poly (PEGDA-co-AN)/LiTFSI/nano SiO 2 with high entropy structure and high conductivity has been designed and fabricated, and it exhibits a room temperature ionic conductivity of 3.5×10 −3 S cm −1 , Li + transference number of 0.58, and the electrochemical stability window greater than 5 V. High entropy electrolytes Polymer composite electrolytes Lewis acid-base interactions Li+ transport All solid state lithium batteries Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 INTRODUCTION Replacing traditional liquid electrolytes with high-performance solid electrolytes to assemble a cell can not only eliminate the risk of electrolyte leakage, effectively suppress the growth of lithium dendrites in lithium batteries during the charging and discharging process, and improve the safety of battery usage, but also can directly use metal lithium as cathode of the battery, then greatly improving the energy density of the batter 1, 2 . To research and develop the high-performance all-solid-state rechargeable batteries with good safety, high energy density and wide operating temperature range becomes a mainstream direction for the next generation saving energy devices. A large number of studies and experiments in the early stage have formed a consensus that the ion transport performance of solid-state electrolytes at room temperature or below and the interface issue between the solid-state electrolytes and electrodes are the bottleneck restricting the further development of all-solid-state batteries 3 . Therefore, it is of practical application and academic valuable to study high-performance all-solid-state electrolytes and the strategies to regulate ion transport in solid-state electrolytes 4, 5 . Commonly, solid electrolytes are able to be divided into three types based on their composition, i.e. Solid inorganic electrolyte (SIE), Solid polymer electrolyte (SPE), and Solid organic-inorganic composite electrolyte (CE). SIEs have good thermal stability, excellent mechanical strength, and high ionic conductivity at room temperature, but their brittleness and poor process-ability are obvious, which is hard to large-scale production. SPEs have good interface contact with the electrodes and are prone to plasticity, making them suitable for large-scale production. However, their ionic conductivity at room temperature is low; organic-inorganic composite solid electrolytes can collect the advanced performance of polymer electrolytes and inorganic solid electrolytes together, and now it has been widely used to improve the interface and mechanical properties of PEO-based electrolyte systems, the related research has received widespread attention from researchers 6 . As a common organic component in CE, polyethylene oxide (PEO) based polymers have good solvation for most lithium salts and are the most widely studied polymer electrolyte substrates in published literature 7 . Lithium ions are transported by coordination/dissociation with PEO ether oxygen atoms and accompanied by motion of PEO segment 8 . However, the high crystallinity of PEO at room temperature limits the motion of PEO polymer segments, resulting in low ionic conductivity at room temperature（10 −8 ~10 −6 S cm −1 ） 9, 10 ; On the other hand, the Electrochemical Stability Window (ESW) of PEO is usually lower than 3.7 V, which restricts the application of some advanced cathode materials with high potential in batteries, thus limiting the improvement of the batteries performance, such as specific capacity, energy density, charge discharge and cycle performance 11, 12 . Polyacrylonitrile (PAN) has high dielectric constant, excellent mechanical and thermal performances, flame retardancy, wide electrochemical window, and is easy to form films 13 . There is not only interaction between Li + and nitrile group (-CN), but also PAN can promote the dissociation of lithium salts due to its high dielectric constant and increase the concentration of charge carrier Li + , which is beneficial for reducing concentration polarization 14 . SiO 2 , TiO 2 , LZTO, etc. are commonly inorganic filler used in organic-inorganic composite electrolyte systems 15 , the inert filler can promote the dissociation of lithium salts and hinder the migration of anion in the electrolyte through Lewis acid-base interaction 16, 17 , even forming a long-range "space charge zone" to promote the transportation of lithium ions 18 ; inorganic active fillers can independently participate in the transportation of lithium ions, but the cost is too high 19 . Lin et al . obtained PEO:LiClO 4 /SiO 2 composite electrolyte( EO/Li = 8:1,mass ratio) by adding 10 wt.% nano-SiO 2 to PEO, which has a ionic conductivity of 1.2 mS cm -1 at 60℃ and a wide electrochemical window of 5.5 V 20 . Based on this fact, it can be seen that the combination of solid polymer electrolytes and inorganic nanoparticles can significantly improve the Li + conductivity and Li + transference number of solid polymer electrolytes 21, 22 . In this manuscript, the cross-linked copolymer poly (PEGDA-co-AN) is prepared by a free radical random copolymerization using polyethylene glycol diacrylate (PEGDA) and acrylonitrile (AN) as the monomers, and 2,2-azodiisobutyronitrile (AIBN) as a initiator, and a composite polymer electrolyte poly (PEGDA-co-AN) /LiTFSI/nano SiO 2 with high entropy structure and high conductivity has been designed and fabricated. The influence of Lewis acid-base interaction between nano SiO 2 additive and -CN or C-O-C on Li + transport has been investigated, and a new idea is proposed to improve the lithium ion transport in the composite polymer electrolytes by adjusting the local charge environment of polymer electrolytes, and the composite polymer electrolyte poly (PEGDA-co-AN) /LiTFSI/nano SiO 2 obtained exhibits a room temperature ionic conductivity of 3.5×10 −3 S cm −1 , Li + transference number of 0.58, and the electrochemical stability window greater than 5 V. EXPERIMENTAL SECTION Materials Poly(ethylene glycol) diacrylate (PEGDA, Mw: 400) and acrylonitrile(AN, 99%) were purchased from Macklin Biochemical Co. Ltd. Bistrifluoromethanesulfonimide lithium salt (LiTFSI, 99%), silicon dioxide (SiO 2 , 20–50 nm), and azobisisobu tyronitrile (AIBN, 98%) were purchased from Adamas. All of the reagents were not further purified prior to use. Preparation of composite polymer solid electrolyte film sample A solid composite polymer electrolyte film was fabricated using traditional solution casting technology. The detail has been shown in S1 of the Supplementary Material Structural characterization of the polymer, solid polymer electrolyte, and solid composite polymer electrolyte samples The chemical structure was characterized by Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and XRD, respectively for all samples. Their FT-IR spectra were recorded with an INVENIO FT-IR instrument (Bruker, Germany) employing attenuated total reflectance (ATR) technique with the wave number ranging from 500 to 4000 cm − 1 . XPS measurements were performed using Al as the anode, the incident angle is 80°(AXIS-SUPRA, Kratos Analytical, UK). XRD was measured with CuKα radiation (λ = 1.5148 Å) (SmartLab SE, Rigaku, Japan). Thermal analysis of polymer and solid composite polymer electrolyte samples Thermal transition behaviors of the samples were analyzed by differential scanning calorimeter (DSC 200F3, NETZSCH, Germany) in a nitrogen atmosphere at a heating rate of 10℃ min − 1 from − 100 to 150℃. Samples with a typical mass of 5–10 mg were encapsulated in sealed aluminum pans. The thermal stability of the prepared material was characterized by thermogravimetric analysis (TGA, TA Instruments, USA) in a nitrogen atmosphere at 30–800 ℃. Electrochemical characterization of solid composite polymer electrolytes Electrochemical properties of the studied solid electrolytes were characterized with their ionic conductivity, Li + transference number (t Li+ ), Electrochemical Stability Window (ESW), and the electrochemical tests were carried out with the CS350H electrochemical workstation (Wuhan Coaster Instrument Co., Ltd. China). The detail step and process to measure the indexes have been described in S2 of Supplementary Material. RESULTS AND DISCUSSION Design of polymer and the composite polymer electrolytes with high entropy Entropy is an important factor for designing multi-component composite electrolytes, and increasing the disorder of multi-component composite electrolytes can simultaneously improve the mechanical properties and ionic transport performance of the system 23 . The Li + conductivity for electrolyte system is controlled by the concentration and migration rate of Li + , and its magnitude can be calculated as follows: Wherein, n i , q i and µ i represent respectively the number, charge and migrating speed of i charge carrier. The concentration of Li + depends on both the amount of lithium salts solvated by the polymer and their dissociation degree 13 . Therefore, the stronger the solvation of polymers, the easier dissociation of lithium salts, and then the higher the Li + carrier concentration, which will be more benefit to improvement of electrolyte Li + conductivity; the migration rate of Li + mainly depends on the motion of polymer segments and the coordination and dissociation interactions between lithium ion and coordinating atoms on the polymer 24 . The lower the crystallinity of the polymer is, the larger the amorphous region is, and then the better the motion of the chain segments is.This article presents a convenient method for constructing a high entropy structure by introducing various coordination groups into polymer molecular chains (as shown in Fig. 1). Specifically, a branched and cross-linked random copolymer molecule is prepared by random free radical copolymerizating PEGDA with AN in solution, and the disorder of branching and cross-linking structures will be significantly increased due to the difference in reaction activity for the two monomers and polymeric chain free radicals, as well as chain transfer reactions. In addition, adding lithium salts and SiO 2 nano-particles into copolymer poly (PEGDA-co-AN) further increases the disorder structure of the composite and the conformational entropy of the polymer molecules and their segments, therefore greatly reduces the crystallinity of the electrolyte system. On the other hand, the Lewis acid-base interaction between Lewis acidic SiO 2 nano-particles and lithium salt anions inhibits the migration of the anions in the electrolyte and benefits the increase of t Li+ . The composite electrolyte with high entropy obtained by dispersing Lewis acid SiO 2 nano-particles in a low crystallinity polymer electrolyte system will show high conductivity, high ionic transference number, and high electrochemical stability. Structural characterization of high entropy copolymer and the composite polymer electrolytes The chemical structures of the prepared copolymer and the composite polymer electrolyte were characterized by Fourier transform infrared spectroscopy (FT-IR). Figure 2 shows the infrared spectra of the monomers mixture, poly(PEGDA-co-AN) polymer film, poly(PEGDA-co-AN)/ LiTFSI solid electrolyte film, and Poly(PEGDA-co-AN)/LiTFSI/nano SiO 2 composite polymer film. By comparing their characteristic infrared absorption of the monomers mixture and the prepared copolymer, it can be found that the absorption peaks related to the C = C have disappeared in the copolymer, such as the peak of olefin cis = CH out of plane bending at 686 cm − 1 , the peak of olefin trans = CH out of plane bending at 966 cm − 1 and the peak of = CH 2 at 1409 cm − 1 , which indicating that the monomers take place a copolymerization. Besides, the synthesized copolymers can only show swelling in some solvents, such as acetonitrile, dimethylformamide (DMF), cyclohexane, etc. This also proves that copolymers with cross-linked structures are synthesized. For poly(PEGDA-co-AN), the peaks at 2242 cm − 1 ,1728 cm − 1 and 1099 cm − 1 were also detected, which correspond to the stretching vibration characteristic peaks of -CN, -C = O, and C-O-C, respectively. Then, in the IR spectrum of the SPE, the peaks at 1140cm − 1 and 1349cm − 1 correspond to the symmetric and asymmetric stretching vibrations of the S = O in LiTFSI. And the peaks at 1055 cm − 1 and 1184 cm − 1 are the stretching vibration peaks of S-N-S and C-F, respectively. For the CPE, poly(PEGDA-co-AN)/LiTFSI/nanoSiO 2 , the resonances peaks of Si-O-Si and O-Si-O at 468cm − 1 and 808cm − 1 can be also observed, which are characteristic peaks from SiO 2 nano-particle 25 . The condensed state structure of the studied samples was characterized by X-ray diffraction (XRD). The XRD curves of the cross-linked copolymer poly(PEGDA-co-AN), the SPE poly(PEGDA-co-AN)/LiTFSI and the CPE poly(PEGDA-co-AN)/LiTFSI/SiO 2 are shown in Fig. 3 . It can be seen that a broad peak in the range of 2θ = 10° to 30° is characteristic peak of incomplete crystallization (mixed phases the crystalline with amorphous regions) of poly(PEGDA-co-AN) cross-linked polymers 26, 27 . Moreover, after adding lithium salts, the broad XRD peak almost disappeared for the SPE and CPE indicating that the packing structure of the polymer has poor orderliness and a more complex internal structural environment, improving polymer and chain segment mobility. It is very conducive to improving the electrolyte conductivity. The crystall peak of lithium salt LiTFSI around 2θ = 35°, 40°and 50° was not observed as well 28, 29 , indicating that the lithium salt was well dissolved in the polymer. Ionic conductivity of the polymer composite electrolytes with high entropy Based on our previous work 30 on poly(PEGDA-co-AN) copolymer electrolytes to modify its conductivity by optimizing the copolymer composition of using ternary phase diagrams, the SPE poly(PEGDA-co-AN)/LiTFSI and CPE with high-entropy poly(PEGDA-co-AN)/LiTFSI/SiO 2 were prepared with a molar ratio of 1:10, respectively in this paper. Figure 4a shows the variation curve of conductivity of SPE poly(PEGDA-co-AN) /LiTFSI system with lithium salt molar ratio. The room temperature ionic conductivity of the SPE increases with lithium salt molar ratio and reaches a maximum of 1.8 mS cm − 1 when n PEGDA : n AN : n LiTFSI =1:10:4.2 (molar ratio). However, as the proportion of lithium salts continues to increase, their conductivity of the SPEs tends to stabilize or even slightly decrease, indicating that lithium salts have exceeded the limit solubility of polymer solvents. Figure 4b shows the variation curve of the ionic conductivity of poly(PEGDA-co-AN)/LiTFSI/nano SiO 2 CPE obtained by mixing SPE with different ratios of SiO 2 nanoparticle. The experimental results show that when mass fraction of SiO 2 added is about 5%, the CPE can reach the highest conductivity 3.51 mS cm − 1 at 25 ℃, and then began to decrease further increasing SiO 2 mass fraction in CPE. This may be due to the decreased dispersion caused by excessive SiO 2 nanoparticles, which hinders ion transport. Figure 4c shows the conductivity of the high-entropy polymer composite electrolyte as a function of temperature fitted with VTF model. Li + transport behavior in high entropy composite electrolytes The solvation of polymer for different lithium salts and the interaction between lithium ion and different ligands are quite different in an electrolyte. The transportation process of lithium ions is mainly achieved through the coordination and coordination dissociation between lithium ion and coordination atoms during the conformational relaxation of polymer chains. If the interaction between lithium ion and coordination atoms is too strong, lithium ions are not easily dissociated from coordination bonds. Conversely, the coordination force is too weak to achieve lithium ion migration in a long-rang with the thermal motion of polymer chains and their segments, as well as to dissociate from the lithium salt lattice. Therefore, there is a match between different lithium salts and the polymer structure in the electrolyte. For PEO based polymer electrolyte systems, the migration and transport of lithium ion largely depend on the effects of coordination/dissociation between lithium ion and coordinating atoms on polymer chains, as well as on the mobility of polymer PEO molecular chains and their segments. In the aforementioned XRD experimental results, there is not any diffraction peak for the SPE and CPE, confirming that the prepared electrolyte exhibited an amorphous high entropy structure. This condensed structure in electrolytes improves the mobility of polymer molecules and their segments, facilitating the migration and transport of Li + . Wang et al . adopted a new approach to graft poly (vinylidene fluoride co hexafluoropropylene) chains onto polyethylene imine (PEI) with abundant -NH 2 groups, achieving higher modulus and conductivity 23 . Su et al. reported a high-entropy SPE that is obtained by introducing newly designed multifunctional ABC miktoarm star terpolymers into poly(ethylene oxide), improving the Li + transference number and toughness, and inducing stable Li plating/stripping 31 . Hence one can see that whether Li + in the coordinated state can dissociate into free Li + in the polymer and whether free Li + can re-coordinate with other functional groups on the polymer chain or its segment is particularly important for Li + transport. Therefore, for polymer molecules with good segment mobility, efficient Li + transport can be achieved only when the coordination force and coordination dissociation force are matched between the coordinating atoms and Li + , and then enhancing the mobility of polymer molecules. Therefore, regulating the coordination/coordination dissociation between Li + and different coordinating groups are effective strategies for improving ion transport in polymer electrolytes. Figure 5 illustrates the Lewis acid-base interaction between Lewis acid SiO 2 particles and their adjacent polymer chains in the CPE electrolyte system. The Lewis acid-base interaction between Lewis acidic SiO 2 nano-particle dispersed in polymer electrolyte systems and coordination groups on polymer chains (or segments) changes the local charge environment of electrolyte polymer chains and regulates the interaction between coordination atoms and Li + 32 , thereby facilitating the dissociation of Li + in the coordinated state in the electrolyte system 33 . In the micro region without SiO 2 particles, the coordination force between Li + and ether oxygen atoms is stronger than that between Li + and -CN. However, at the interface between SiO 2 particles and polymer matrix, the Lewis acid-base interaction between SiO 2 and C-O is stronger than that between SiO 2 and -CN, resulting in the difference decreasing in coordination ability among Li + and O and N atoms, respectively. Under this effect and external electric field, once the polyether chain or the segment containing -CN takes the relaxation motion in the micro region without SiO 2 particles and approaches to the coordination state Li + around SiO 2 particles, Li + will easily undergo dissociation and re-coordination. Therefore, this effects in coordinated state lithium ions tend to occur around Lewis particles, and make the random process of Li + coordination/coordination dissociation in polymer electrolytes show the “orientation” in a certain degree. Figure 6 shows the characteristic absorption of C-O-C and -CN stretching vibrations of the studied samples. The C-O-C and -CN stretching vibrations located at 1095 cm − 1 and 2241 cm − 1 respectively in the poly(PEGDA-co-AN) cross-linked polymer (without lithium salts and SiO 2 nano-particle). After adding SiO 2 nano-particle into the polymer sample, the characteristic absorption of C-O-C exhibits a red shift, shifting to 1074 cm − 1 from 1095 cm − 1 ; however, the stretching vibration frequency of -CN group did not show a significant change, indicating that the Lewis acid-base interaction between SiO 2 and the -CN group is weaker than that between SiO 2 and the C-O-C group. In addition, for the electrolyte samples containing lithium salt poly(PEGDA-co-AN)/LiTFSI and poly(PEGDA-co-AN)/LiTFSI/SiO 2 , the characteristic absorption frequencies of C-O-C and -CN were significantly higher than those in the poly Poly(PEGDA-co-AN) and Poly(PEGDA-co-AN)/SiO 2 samples without lithium salts, indicating that Li + acts with ether oxygen atom and with N atom of -CN respectively is also significant. In order to further discuss the influence of SiO 2 on Li + coordination, the XPS fine spectra of C, O, and N elements in CPE and SPE were measured, as shown in Fig. 6. It can be observed from Fig. 7a that the binding energy (E B ) of N1s electron shows a increase when lithium salt LiTFSI is added to the polymer to form an electrolyte. This can be attributed to the coordination effect between Li + and -CN, which leads to a stronger electron binding outside the nucleus of the N atom. As shown in Fig. 7b, the O1s E B values of C-O-C and C = O in the copolymer sample are different due to two kinds of chemical environment. However, for the CPE specimen the two O1s peaks corresponding to C-O and C = O almost overlap, and the peak assignment to C-O-C shifts towards higher binding energy, while the O1s binding energy of C = O decreases comparing with that in the copolymer. These results indicate that the two different oxygen atoms in C-O and C = O in CPEs, tend to have consistent O1s electron binding energy after being regulated by the dual effects of SiO 2 and lithium salts, which facilitates the dissociation of coordinated Li + on the copolymer chain. Figure 7c shows C1s fine spectrum in the peaks assignment to C-O-C and -CN related to Li + coordination become wider. This can be explained by the fact that the chemical environment of C-O-C and -CN becomes more complex after interacting with lithium salts and SiO 2 , and thus resulting in wider distribution in C1s binding energy in these different functional groups. The interactions among these functional groups are beneficial for their better synergistic effect in ion transport and for the improvement of conductivity. The Li + transference number (t Li+ ) represents the proportion of lithium ion in all migrated ions, it is another important parameter that characterizes the Li + transport in electrolytes as well. The Li + transference number is not only related to the ionic conductivity of the electrolyte, but also closely related to the Coulombic efficiency and charge/discharge performance of the assembled battery 34 . The higher the Li + transference number, the better the overall performance of the battery 35 . Figure 8 shows the chronoamperometry (CA) and electrochemical impedance spectrum (EIS) of the composite electrolyte. The transference number t Li+ of poly(PEGDA-co-AN) /LiTFSI/SiO 2 CPE was calculated to be approximately 0.58 using the Bruce Vincent Evans (BVE) formula. Figure 9 shows the characteristic infrared absorption of TFSI − in SPE and CPE, where the characteristic absorption at 740 cm − 1 corresponds to the S-N-S stretching vibration in TFSI − in both electrolytes. This peak can be split into the free state TFSI − located at approximately 738 cm − 1 and the bound state TFSI − located at approximately 742 cm − 1 using a software 36 . By comparing the split areas of TFSI − peaks, it can be found that the peak area of bound TFSI − in CPE is larger than that in the SPE. This is due to the Lewis acid-base interaction between Lewis acid SiO 2 and TFSI − , which is capable to inhibiting TFSI − movement in the electrolyte under an external electric field. Based on this, it can be seen that the Lewis acid-base interaction between uniformly dispersed nano SiO 2 particles and TFSI − is beneficial for improving the Li + transference number. The analysis based on XRD, FT-IR, and XPS results suggests that SiO 2 in composite polymer electrolytes not only contributes to the high entropy properties of the system, inhibits the crystallization of PEO segments, improves the mobility of polymer segments, but also regulates the local charge environment between polymer molecules and their segments. Through Lewis acid-base interactions, the coordination and dissociation abilities in the composite electrolyte system are also regulated between lithium ions and the polymer coordination groups, such as -CN, C-O-C and C = O etc. This effect improves the conductivity of the electrolyte, and SiO 2 can inhibit the migration of lithium salt anions in the electrolyte, ultimately improving the Li + transport ability of the electrolyte. Stability of high entropy composite polymer electrolytes The thermal stability and electrochemical stability of the electrolyte directly affects the safety of battery usage. The thermal stability of these studied samples was characterized by TGA and their TGA curves are shown in Fig. 10. It can be found that their thermal decomposition temperatures are more than 300 ℃ for both the polymer and the electrolyte. The electrochemical stability was characterized by linear cyclic voltammetry (CV) scanning technology to determine the electrochemical stability window of the electrolyte. Figure 11 shows the CV scanning curves of a lithium stainless steel half cell assembled with poly (PEGDA-co-AN)/LiTFSI SPE and Poly (PEGDA-co-AN)/LiTFSI/SiO 2 CPE, respectively. The CPE exhibits good electrochemical stability, and without significant redox peaks below 5 V. The wide electrochemical stability window of the electrolyte can be attributed to the introduction of AN monomers with high dielectric constants in polymer structure. The highly polar -CN in the polymer effectively reduces the electron density of its adjacent ester group (COO − ) and improves overall oxidation resistance. On the other hand, the withdrawing electron effect from -CN can suppress the frontier orbital electron from concentrating on the ester group but also distributes on AN segments 37 . Delocalization of frontier electrons is helpful for avoiding an oxidation reaction to take place on a certain position. In adding, that TFSI − anion is bounded by SiO 2 reduces the decomposition of anionic TFSI − near the electrode, resulting in better electrochemical stability of the electrolyte. CONCLUSION Polymers with high dielectric constants have a strong solvation action on lithium salts. The ether oxygen atoms in PEO polymers have strong coordination with alkali metal lithium ion, but for PEO-based polymers their chains relaxation is difficult due to high crystallinity at room temperature; PAN has high electrochemical and thermal stability, good mechanical and processing properties, as well as good flame retardancy. In this paper, a crossing-linked copolymer poly(PEGDA-co-AN) and its composite polymer electrolyte poly(PEGDA-co-AN)/LiTFSI/nano-SiO 2 with a high entropy structure and high conductivity were designed and prepared. The structures of the copolymers and the key indexes of the composite polymer electrolytes were characterized, respectively. The Lewis acid-base interactions of -CN and C-O with nano SiO 2 in the polymer electrolyte system and the actions on the behavior of Li + coordination/coordination dissociation were studied using XRD, FT-IR, and XPS. It is believed that the Lewis acid-base interaction of SiO 2 nano-particles with ether-oxygen atoms and -CN groups in the copolymer reduces the strong coordination force between Li + and ether-oxygen atoms, and leads to the averaging effect of Li + coordination with -CN and C-O, respectively. In addition, Lewis acid nano-SiO 2 also inhibits the migration of lithium anion TFSI − under an external electric field. A new strategy was proposed to improve the lithium ion transport performance in composite polymer electrolytes by adding appropriate amount of SiO 2 nano-particle to regulate the local charge environment of the polymer in poly (PEGDA-co-AN) /LiTFSI electrolyte system, and a high entropy structure composite polymer electrolyte, poly (PEGDA-co-AN) /LiTFSI/nano SiO 2 , was successfully fabricated which has a high room temperature ionic conductivity of 3.5×10 − 3 S cm − 1 , Li + transference number of 0.58, and an electrochemical window greater than 5 V. Declarations Confict of interest The authors declare that they have no conficts of interest related to the content of this research. ACKNOWLEDGMENTS The authors thank Professor Zou Qichao in Hubei University who assisted in thermal analysis, and Zhang Guohong, PhD in Test & Analysis Central of Wuhan University of Science and Technology who assisted in XPS, XRD, and FT-IR test. Author contributions YF.Z conducted major experiments and characterization content, prepared all the images and wrote the article manuscript; X.W participated in sample preparation and contributed to the data collection and analysis ; S.PJ was responsible for the overall planning, design and implementation of the study, and supervised and coordinated the entire study.All authors reviewed the manuscript. Data availability No datasets were generated or analysed during the current study. References Cheng X-B, Zhang R, Zhao C-Z, Zhang Q. Toward Safe Lithium Metal Anode in Rechargeable Batteries: A Review. Chemical Reviews. 2017;117: 10403-10473. http://dx.doi.org/10.1021/acs.chemrev.7b00115 Shen Y, Zhang Y, Han S, Wang J, Peng Z, Chen L. Unlocking the Energy Capabilities of Lithium Metal Electrode with Solid-State Electrolytes. Joule. 2018;2: 1674-1689. http://dx.doi.org/10.1016/j.joule.2018.06.021 Jin Y, Yu H, Gao Y, Liang X. 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Chemical Physics Letters. 2003;378: 299-304. http://dx.doi.org/10.1016/j.cplett.2003.07.015 Yu X, Xue L, Goodenough JB, Manthiram A. All‐Solid‐State Sodium Batteries with a Polyethylene Glycol Diacrylate–Na 3 Zr 2 Si 2 PO 12 Composite Electrolyte. Advanced Energy and Sustainability Research. 2020;2. http://dx.doi.org/10.1002/aesr.202000061 Liu B, Xu Z, Fan C, et al. A Solvent‐Free and Water‐Resistant Dipole–Dipole Interaction‐Based Super Adhesive. Macromolecular Rapid Communications. 2021;42. http://dx.doi.org/10.1002/marc.202100010 Li W, Ma L, Liu S, et al. Thermally Depolymerizable Polyether Electrolytes for Convenient and Low‐Cost Recycling of LiTFSI. Angewandte Chemie International Edition. 2022;61. http://dx.doi.org/10.1002/anie.202209169 Whitfield PS, Abouimrane A, Davidson IJ. In-situ XRD study of the succinonitrile–lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) phase diagram. Solid State Ionics. 2010;181: 740-744. http://dx.doi.org/10.1016/j.ssi.2010.04.004 Wu X, Zhang Y, Peng S. An ambient‐temperature superionic conductive, electrochemically stable, plastic cross‐linked polymer electrolyte for lithium metal battery. Journal of Applied Polymer Science. 2024;141. http://dx.doi.org/10.1002/app.55234 Su Y, Rong X, Li H, et al. High‐Entropy Microdomain Interlocking Polymer Electrolytes for Advanced All‐Solid‐State Battery Chemistries. Advanced Materials. 2022;35. http://dx.doi.org/10.1002/adma.202209402 Liu S, Liu W, Ba D, et al. Filler‐Integrated Composite Polymer Electrolyte for Solid‐State Lithium Batteries. Advanced Materials. 2022;35. http://dx.doi.org/10.1002/adma.202110423 Zhaoxiang Wang, Biying Huang, Rongjian Xue, Xuejie Huang, Chen* L. Spectroscopic investigation of interactions among components and ion transport mechanism in polyacrylonitrile based electrolytes. Solid State Ionics. 1999;121: 141-156. http://dx.doi.org/10.1016/s0167-2738(98)00541-4 Zhu J, Zhang Z, Zhao S, Westover AS, Belharouak I, Cao PF. Single‐Ion Conducting Polymer Electrolytes for Solid‐State Lithium–Metal Batteries: Design, Performance, and Challenges. Advanced Energy Materials. 2021;11. http://dx.doi.org/10.1002/aenm.202003836 Meng N, Ye Y, Yang Z, Li H, Lian F. Developing Single‐Ion Conductive Polymer Electrolytes for High‐Energy‐Density Solid State Batteries. Advanced Functional Materials. 2023;33. http://dx.doi.org/10.1002/adfm.202305072 Liu K, Cheng H, Wang Z, et al. A 3 µm‐Ultrathin Hybrid Electrolyte Membrane with Integrative Architecture for All‐Solid‐State Lithium Metal Batteries. Advanced Energy Materials. 2024;14. http://dx.doi.org/10.1002/aenm.202303940 Tang L, Chen B, Zhang Z, et al. Polyfluorinated crosslinker-based solid polymer electrolytes for long-cycling 4.5 V lithium metal batteries. Nature Communications. 2023;14. http://dx.doi.org/10.1038/s41467-023-37997-6 Additional Declarations No competing interests reported. Supplementary Files Supplementarymaterial.doc Cite Share Download PDF Status: Published Journal Publication published 15 Oct, 2024 Read the published version in Polymer Bulletin → Version 1 posted Editorial decision: Revision requested 27 Aug, 2024 Reviews received at journal 24 Aug, 2024 Reviewers agreed at journal 12 Aug, 2024 Reviewers invited by journal 12 Aug, 2024 Editor assigned by journal 05 Jul, 2024 Submission checks completed at journal 04 Jul, 2024 First submitted to journal 03 Jul, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4682986","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":326534647,"identity":"b4848a3d-ef59-4c1b-bef4-3336e0046d17","order_by":0,"name":"Yafei Zhang","email":"","orcid":"","institution":"Wuhan University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Yafei","middleName":"","lastName":"Zhang","suffix":""},{"id":326534651,"identity":"1d7bc617-6a47-4349-990d-c8510c003a4d","order_by":1,"name":"Xiao Wu","email":"","orcid":"","institution":"Wuhan University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Xiao","middleName":"","lastName":"Wu","suffix":""},{"id":326534653,"identity":"9915b030-493d-4820-b831-ef6ab7e6cb96","order_by":2,"name":"Shunjin Peng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+ElEQVRIiWNgGAWjYLACxgYgbmZgfADlGxCthRmkVIJ4LUDAJkGUFnP23sMvf+44nMfcznusmretro6BvXmbBEPNHZxaLHvOpVnznjlczNjMl3abt+2wBAPPsTIJhmPPcGoxuJFjZszYdjixsZnH7HZu2wEJBokcMwnGhsO4tdx/Y2b4E6qlOLetToJB/g0BLTd4jB/wQrUw57YxA23hwa/FsifHjJm3LR2kxVj6z7nDkm08acUWCcdwazFnP2P88WebdeLG/jOGH2eU1fHzsx/eeONDDR6HQaODwbABKsIGIhJwagBrYf4AYsjjUTQKRsEoGAUjHAAAMzVRdiNIANgAAAAASUVORK5CYII=","orcid":"","institution":"Wuhan University of Science and Technology","correspondingAuthor":true,"prefix":"","firstName":"Shunjin","middleName":"","lastName":"Peng","suffix":""}],"badges":[],"createdAt":"2024-07-04 00:44:51","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4682986/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4682986/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00289-024-05540-2","type":"published","date":"2024-10-15T15:56:55+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":61311469,"identity":"29758bc6-4087-496b-b28a-b3a26058b42a","added_by":"auto","created_at":"2024-07-29 11:09:18","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":92048,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of high entropy polymer construction\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/ec47e83b4adfc2c4fb25a9c4.png"},{"id":61310834,"identity":"c3126d3f-a1ed-4718-85d5-1e005e7f0717","added_by":"auto","created_at":"2024-07-29 11:01:18","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":93116,"visible":true,"origin":"","legend":"\u003cp\u003eInfrared spectra of the series of samples\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/70023fdb76faea78f7750fbd.png"},{"id":61310822,"identity":"16d20c48-cb29-4aa0-a4e8-0cbd7653a038","added_by":"auto","created_at":"2024-07-29 11:01:16","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":49146,"visible":true,"origin":"","legend":"\u003cp\u003eXRD spectra of the different samples\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/8bf9b7862819c58d2b6d3b5c.png"},{"id":61310826,"identity":"9a724fa4-40f8-487d-928a-47c236e6c16d","added_by":"auto","created_at":"2024-07-29 11:01:17","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":61621,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea) \u003c/strong\u003eThe variation curve of SPE conductivity with lithium salt molar ratio; \u003cstrong\u003eb)\u003c/strong\u003e The variation curve of the conductivity of CPE with the proportion of nano SiO\u003csub\u003e2\u003c/sub\u003e; \u003cstrong\u003ec)\u003c/strong\u003e VTF fitting of ionic conductivity of SPE and CPE with temperature variation.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/9725fecfab1d75da7c4e918a.png"},{"id":61311468,"identity":"58c708c4-4d66-437c-973f-46795daa64c4","added_by":"auto","created_at":"2024-07-29 11:09:18","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":252966,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagrams of Lewis acid-base interactions between SiO\u003csub\u003e2\u003c/sub\u003e and polymer segments and interactions between different coordinating groups\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/8dfa2b3b7bb9dca4f62686f6.png"},{"id":61311466,"identity":"0e6838a8-9859-4db1-bf70-f4d17ad48ade","added_by":"auto","created_at":"2024-07-29 11:09:17","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":120851,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of infrared characteristic absorption of C-O-C and -CN in different samples\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/7fe8a20cf5d35a45fd4abc69.png"},{"id":61310840,"identity":"3405b611-ed82-43b2-9e72-f16326be9dfc","added_by":"auto","created_at":"2024-07-29 11:01:18","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":150371,"visible":true,"origin":"","legend":"\u003cp\u003eXPS fine spectra of C1s, O1s, and N1s in poly (PEGDA-co-AN) and poly (PEGDA-co-AN)/LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e composite electrolytes\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/67619baf02bbfc3ce613a0b2.png"},{"id":61310842,"identity":"528259d8-c148-4a20-85d3-fcbf042a6288","added_by":"auto","created_at":"2024-07-29 11:01:18","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":39537,"visible":true,"origin":"","legend":"\u003cp\u003eCA curve of CPE at 25℃\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/e9930e4ff7d3051fd5a8a087.png"},{"id":61310830,"identity":"60540544-1871-4cd2-873c-ecdfd5e2a606","added_by":"auto","created_at":"2024-07-29 11:01:17","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":50472,"visible":true,"origin":"","legend":"\u003cp\u003eThe infrared characteristic absorption of TFSI\u003csup\u003e-\u003c/sup\u003e group\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/4d8b605f3a39a4c4562337e9.png"},{"id":61311467,"identity":"59c0aa38-d244-4bc7-b939-ee2f06b205d3","added_by":"auto","created_at":"2024-07-29 11:09:18","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":42892,"visible":true,"origin":"","legend":"\u003cp\u003eThermogravimetric analysis of polymer and CPE\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/855db9d90c6434e788699aec.png"},{"id":61310824,"identity":"4c9335d4-fc44-4a73-af06-9f69d8021a4b","added_by":"auto","created_at":"2024-07-29 11:01:17","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":67161,"visible":true,"origin":"","legend":"\u003cp\u003eLSV curves of SPE and CPE\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/e121ca79e4fa5e4022b5539d.png"},{"id":67148932,"identity":"e8527ade-2848-4aca-9ab7-f10676a60d3b","added_by":"auto","created_at":"2024-10-21 16:10:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1543304,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/20d29314-5f2f-41b0-8236-97b9dfd18170.pdf"},{"id":61310823,"identity":"01e1d6eb-fefa-4eb2-bea2-cd86d2bd6dd1","added_by":"auto","created_at":"2024-07-29 11:01:16","extension":"doc","order_by":15,"title":"","display":"","copyAsset":false,"role":"supplement","size":27648,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.doc","url":"https://assets-eu.researchsquare.com/files/rs-4682986/v1/792aff12453ba451d3330d0f.doc"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eA solid composite electrolyte poly(PEGDA-co-AN)/ LiTFSI/nano SiO\u003csub\u003e2 \u003c/sub\u003ewith high conductivity and high entropy structure and its Li\u003csup\u003e+\u003c/sup\u003e transport behavior\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eReplacing traditional liquid electrolytes with high-performance solid electrolytes to assemble a cell can not only eliminate the risk of electrolyte leakage, effectively suppress the growth of lithium dendrites in lithium batteries during the charging and discharging process, and improve the safety of battery usage, but also can directly use metal lithium as cathode of the battery, then greatly improving the energy density of the batter\u003csup\u003e1, 2\u003c/sup\u003e. To research and develop the high-performance all-solid-state rechargeable batteries with good safety, high energy density and wide operating temperature range becomes a mainstream direction for the next generation saving energy devices. A large number of studies and experiments in the early stage have formed a consensus that the ion transport performance of solid-state electrolytes at room temperature or below and the interface issue between the solid-state electrolytes and electrodes are the bottleneck restricting the further development of all-solid-state batteries\u003csup\u003e3\u003c/sup\u003e. Therefore, it is of practical application and academic valuable to study high-performance all-solid-state electrolytes and the strategies to regulate ion transport in solid-state electrolytes\u003csup\u003e4, 5\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eCommonly, solid electrolytes are able to\u0026nbsp;be divided into three types based on their composition, i.e.\u0026nbsp;Solid inorganic electrolyte (SIE),\u0026nbsp;Solid polymer electrolyte (SPE), and\u0026nbsp;Solid organic-inorganic composite electrolyte (CE). SIEs have good thermal stability, excellent mechanical strength, and high ionic\u0026nbsp;conductivity at room temperature, but their brittleness and poor process-ability are obvious, which is hard to large-scale production. SPEs have good interface contact with the electrodes\u0026nbsp;and are prone to plasticity, making them suitable for large-scale production. However, their ionic conductivity\u0026nbsp;at room temperature is low; organic-inorganic composite solid electrolytes can collect\u0026nbsp;the advanced performance of polymer electrolytes and inorganic solid electrolytes together, and now it has been widely used to improve the interface and mechanical properties of PEO-based electrolyte systems, the related research has received widespread attention from researchers\u003csup\u003e6\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eAs a common organic component in CE, polyethylene oxide (PEO) based polymers have good solvation for most lithium salts and are the most widely studied polymer electrolyte substrates in published literature\u003csup\u003e7\u003c/sup\u003e. Lithium ions are transported by coordination/dissociation with PEO ether oxygen atoms and accompanied by motion of PEO segment\u003csup\u003e8\u003c/sup\u003e. However, the high crystallinity of PEO at room temperature limits the\u0026nbsp;motion\u0026nbsp;of PEO polymer segments, resulting in low ionic conductivity at room temperature（10\u003csup\u003e\u0026minus;8\u003c/sup\u003e~10\u003csup\u003e\u0026minus;6\u003c/sup\u003e S cm\u003csup\u003e\u0026minus;1\u003c/sup\u003e）\u003csup\u003e9, 10\u003c/sup\u003e; On the other hand, the Electrochemical Stability Window (ESW) of PEO is usually lower than 3.7 V, which restricts the application of some advanced cathode materials with high potential in batteries, thus limiting the improvement of\u0026nbsp;the batteries performance,\u0026nbsp;such as specific capacity, energy density, charge discharge and cycle performance\u003csup\u003e11, 12\u003c/sup\u003e. Polyacrylonitrile (PAN) has high dielectric constant, excellent mechanical and thermal performances, flame retardancy, wide electrochemical window, and is easy to form films\u003csup\u003e13\u003c/sup\u003e. There is not only interaction between Li\u003csup\u003e+\u003c/sup\u003e\u003csup\u003e\u0026nbsp;\u003c/sup\u003eand nitrile group (-CN), but also PAN can promote the dissociation of lithium salts due to its high dielectric constant and increase the concentration of charge carrier Li\u003csup\u003e+\u003c/sup\u003e, which is beneficial for reducing concentration polarization\u003csup\u003e14\u003c/sup\u003e. SiO\u003csub\u003e2\u003c/sub\u003e, TiO\u003csub\u003e2\u003c/sub\u003e, LZTO, etc. are commonly inorganic filler used in organic-inorganic composite electrolyte systems\u003csup\u003e15\u003c/sup\u003e, the inert filler can promote the dissociation of lithium salts and hinder the migration of anion in the electrolyte through Lewis acid-base interaction\u003csup\u003e16, 17\u003c/sup\u003e, even forming a long-range \u0026quot;space charge zone\u0026quot; to promote the transportation of lithium ions\u003csup\u003e18\u003c/sup\u003e; inorganic active fillers can independently participate in the transportation of lithium ions, but the cost is too high\u003csup\u003e19\u003c/sup\u003e. Lin\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e\u003cem\u003e.\u003c/em\u003e obtained PEO:LiClO\u003csub\u003e4\u003c/sub\u003e/SiO\u003csub\u003e2\u003c/sub\u003e composite electrolyte( EO/Li = 8:1,mass ratio) by adding 10 wt.% nano-SiO\u003csub\u003e2\u003c/sub\u003e to PEO, which has a ionic conductivity of 1.2 mS cm\u003csup\u003e-1\u003c/sup\u003e at 60℃ and a wide electrochemical window of 5.5 V\u0026nbsp;\u003csup\u003e20\u003c/sup\u003e.\u0026nbsp; Based on this fact, it can be seen that the combination of solid polymer electrolytes and inorganic nanoparticles can significantly improve the Li\u003csup\u003e+\u003c/sup\u003econductivity and Li\u003csup\u003e+\u003c/sup\u003e transference number of solid polymer electrolytes \u003csup\u003e21, 22\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIn this manuscript, the cross-linked copolymer poly (PEGDA-co-AN) is prepared by a free radical random copolymerization\u0026nbsp;using polyethylene glycol diacrylate (PEGDA) and acrylonitrile (AN) as the monomers, and 2,2-azodiisobutyronitrile (AIBN) as a initiator, and a composite polymer electrolyte poly (PEGDA-co-AN) /LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e with high entropy structure and high conductivity has been designed and fabricated. The influence of Lewis acid-base interaction between nano SiO\u003csub\u003e2\u003c/sub\u003e additive and -CN or C-O-C on Li\u003csup\u003e+\u003c/sup\u003e transport has been investigated, and a new idea is proposed to improve the lithium ion transport in the composite polymer electrolytes by adjusting the local charge environment of polymer electrolytes, and the composite polymer electrolyte poly (PEGDA-co-AN) /LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e obtained exhibits a room temperature ionic conductivity of 3.5\u0026times;10\u003csup\u003e\u0026minus;3\u003c/sup\u003e S cm\u003csup\u003e\u0026minus;1\u003c/sup\u003e, Li\u003csup\u003e+\u003c/sup\u003e transference number of 0.58, and the electrochemical stability window greater than 5 V.\u003c/p\u003e"},{"header":"EXPERIMENTAL SECTION","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eMaterials\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003ePoly(ethylene glycol) diacrylate (PEGDA, Mw: 400) and acrylonitrile(AN, 99%) were purchased from Macklin Biochemical Co. Ltd. Bistrifluoromethanesulfonimide lithium salt (LiTFSI, 99%), silicon dioxide (SiO\u003csub\u003e2\u003c/sub\u003e, 20\u0026ndash;50 nm), and azobisisobu tyronitrile (AIBN, 98%) were purchased from Adamas. All of the reagents were not further purified prior to use.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003ePreparation of composite polymer solid electrolyte film sample\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eA solid composite polymer electrolyte film was fabricated using traditional solution casting technology. The detail has been shown in S1 of the Supplementary Material\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStructural characterization of the polymer, solid polymer electrolyte, and solid composite polymer electrolyte samples\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe chemical structure was characterized by Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and XRD, respectively for all samples. Their FT-IR spectra were recorded with an INVENIO FT-IR instrument (Bruker, Germany) employing attenuated total reflectance (ATR) technique with the wave number ranging from 500 to 4000 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. XPS measurements were performed using Al as the anode, the incident angle is 80\u0026deg;(AXIS-SUPRA, Kratos Analytical, UK). XRD was measured with CuKα radiation (λ\u0026thinsp;=\u0026thinsp;1.5148 \u0026Aring;) (SmartLab SE, Rigaku, Japan).\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eThermal analysis of polymer and solid composite polymer electrolyte samples\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThermal transition behaviors of the samples were analyzed by differential scanning calorimeter (DSC 200F3, NETZSCH, Germany) in a nitrogen atmosphere at a heating rate of 10℃ min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e from \u0026minus;\u0026thinsp;100 to 150℃. Samples with a typical mass of 5\u0026ndash;10 mg were encapsulated in sealed aluminum pans.\u003c/p\u003e \u003cp\u003eThe thermal stability of the prepared material was characterized by thermogravimetric analysis (TGA, TA Instruments, USA) in a nitrogen atmosphere at 30\u0026ndash;800 ℃.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eElectrochemical characterization of solid composite polymer electrolytes\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eElectrochemical properties of the studied solid electrolytes were characterized with their ionic conductivity, Li\u003csup\u003e+\u003c/sup\u003e transference number (t\u003csub\u003eLi+\u003c/sub\u003e), Electrochemical Stability Window (ESW), and the electrochemical tests were carried out with the CS350H electrochemical workstation (Wuhan Coaster Instrument Co., Ltd. China). The detail step and process to measure the indexes have been described in S2 of Supplementary Material.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS AND DISCUSSION","content":"\u003cdiv id=\"Sec9\"\u003e\n \u003ch2\u003eDesign of polymer and the composite polymer electrolytes with high entropy\u003c/h2\u003e\n \u003cdiv\u003e\n \u003cp\u003eEntropy is an important factor for designing multi-component composite electrolytes, and increasing the disorder of multi-component composite electrolytes can simultaneously improve the mechanical properties and ionic transport performance of the system\u003csup\u003e23\u003c/sup\u003e. The Li\u003csup\u003e+\u003c/sup\u003e conductivity for electrolyte system is controlled by the concentration and migration rate of Li\u003csup\u003e+\u003c/sup\u003e, and its magnitude can be calculated as follows:\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv id=\"Equ1\"\u003e\n \u003cdiv\u003e\u003cimg src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAYMAAAAeCAYAAADO63I7AAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAAUQSURBVHhe7dxLKHxtHAfwx/uWhdijXMclG7mUhdi4hSgbl5RLKcKCRi7Ll437ZYNcFm5FLCmSImMhCtnINSnDwkLGgo155/f7P/M243/O+c+M9/83w/dTpznPOfOMYfF8z/M7z+FlthAAAPCt/SVfAQDgG0MYAAAAwgAAABAGAABggTAAAADPCIP+/n7h5eXl0FZRUSF7AQCAozwiDJqamkRfXx/vl5eXC5PJJGhF7Pvt4OBAvLy8iOfnZ34vAAA45u9/LOS+W0tOThZ+fn6it7dX3N7eiszMTOHt7S3P/hAQECCenp5ESEgIvxcAAByjOTOgK+zq6mq3KcNYZwgzMzOivr5ecQZQVVXFoeCMu7s7DpfJyUn+HTMyMlyaXVAf+o70GYODgyI6OlocHh7Ks8qsfaw/0/pd6BUA4E9RDQMamGhgLSgo4LJMR0cHv05PT8t3OIY+hwY620Cxbq4ECw2cer3+v0D4KPp+ZWVlYmNjQxgMBmE0Gnl2cX5+Lt/hOPo+Dw8P/Hd6e3sTQUFBIjIyUp5VRj8nPT2dfyb1u7+/F7GxsU4HGgDAR6iGwdjYmEhKShK5ubnC19dXPD4+ujRAUl8aaJVq/M4GixXdULYGwkdnKvT9ZmdnObC6urq4vBQWFibPOm5lZYXLV8PDw/yZx8fHIicnh/e1xMfHi5OTExETE8MBMDQ0JAIDA+VZAABldXV1YmFhQbaEuLq64ovsnp4eeeTHsYiICNnSphoGNJhRmYNQyYLa/v7+3HbG/z0zsGpvb+cr6sLCQnnkcy0tLYnGxkYe/Kk0tLu7K9LS0uRZdfT3WV1d5d+DwpaCwZF+APB90QAfGhoqSkpKuE0BoNPpeN9WeHi4mJqa4vGWgkGL5j2D09NTHqzGx8ddLl38jpkB2dra4ivvvLw8eeTPuri4kHv2KAhGR0c1S0S2fSkAqERkvb8QFxfnUD8A+J5oRkD3cltaWuQRwfs0pipJSUnhEnhWVpY8okw1DOh+QWdnJ5dNaLCiK3F3QYMmlXZqamrkkY9pa2vjwKJXKo8tLi6K5uZmDkI176deFJb5+flibm5OvL6+apaIbPtSaYlQKPj4+IijoyNeIqvE0ekeAHxNOzs7fLFpGwSOoECgMLAtIf3EkiYexWg0mouLi/n1s1gGa/PExIRs2TOZTOaioiJ+jxKtvlpc7QcAX0dtbS1vamhI7+7uli178/PzZp1OJ1s/0ywTuSNaWtra2vqpq21o1U9iYqJs2bPeZFcr9Wj11eJqPwD4OtbX1/legStoQdDl5aXqvQOPCgNaRUQrbWgFjhpa1UPb77S5ualYQqLvl5CQwGUmKjcpUev7K672A4Cvgwbz4OBg2XINLZ9XJGcIbm95edms1+tlS9nZ2Zk5OztbtUQDAODJaMimco8aOq9WJrIECZ83GAzyiD2PmBnQ0taGhgYxMDBgtzT1/RYVFSX29/dlLwCAr4WWj97c3MiWa9SeY/KIMKD7AzQ9soTXLzd6AlirjAQA4KloRdD19bVsOWdvb4/DhJ49UOJxN5ABAL6r0tJSXlr6Hj2JTNURQgtslJahb29v8/MJarwsV9PKTyoAAIDboYfOaEWRM88a0AoimhVoDfcIAwAAD5Odnc3lnpGREXlEHT2olpqayqV2tRIRQZkIAMDDrK2t8ezA9h/VKaEZQWVlJc8ItIKAYGYAAACYGQAAAMIAAAAsEAYAAIAwAAAAIf4FZ7oNU/zNW5IAAAAASUVORK5CYII=\" width=\"387\" height=\"30\"\u003e\u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eWherein, n\u003csub\u003ei\u003c/sub\u003e, q\u003csub\u003ei\u003c/sub\u003e and \u0026micro;\u003csub\u003ei\u003c/sub\u003e represent respectively the number, charge and migrating speed of i charge carrier. The concentration of Li\u003csup\u003e+\u003c/sup\u003e depends on both the amount of lithium salts solvated by the polymer and their dissociation degree\u003csup\u003e13\u003c/sup\u003e. Therefore, the stronger the solvation of polymers, the easier dissociation of lithium salts, and then the higher the Li\u003csup\u003e+\u003c/sup\u003e carrier concentration, which will be more benefit to improvement of electrolyte Li\u003csup\u003e+\u003c/sup\u003e conductivity; the migration rate of Li\u003csup\u003e+\u003c/sup\u003e mainly depends on the motion of polymer segments and the coordination and dissociation interactions between lithium ion and coordinating atoms on the polymer\u003csup\u003e24\u003c/sup\u003e. The lower the crystallinity of the polymer is, the larger the amorphous region is, and then the better the motion of the chain segments is.This article presents a convenient method for constructing a high entropy structure by introducing various coordination groups into polymer molecular chains (as shown in Fig.\u0026nbsp;1). Specifically, a branched and cross-linked random copolymer molecule is prepared by random free radical copolymerizating PEGDA with AN in solution, and the disorder of branching and cross-linking structures will be significantly increased due to the difference in reaction activity for the two monomers and polymeric chain free radicals, as well as chain transfer reactions. In addition, adding lithium salts and SiO\u003csub\u003e2\u003c/sub\u003e nano-particles into copolymer poly (PEGDA-co-AN) further increases the disorder structure of the composite and the conformational entropy of the polymer molecules and their segments, therefore greatly reduces the crystallinity of the electrolyte system. On the other hand, the Lewis acid-base interaction between Lewis acidic SiO\u003csub\u003e2\u003c/sub\u003e nano-particles and lithium salt anions inhibits the migration of the anions in the electrolyte and benefits the increase of t\u003csub\u003eLi+\u003c/sub\u003e. The composite electrolyte with high entropy obtained by dispersing Lewis acid SiO\u003csub\u003e2\u003c/sub\u003e nano-particles in a low crystallinity polymer electrolyte system will show high conductivity, high ionic transference number, and high electrochemical stability.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003ch3\u003eStructural characterization of high entropy copolymer and the composite polymer electrolytes\u003c/h3\u003e\n\u003cdiv\u003e\n \u003cp\u003eThe chemical structures of the prepared copolymer and the composite polymer electrolyte were characterized by Fourier transform infrared spectroscopy (FT-IR). Figure\u0026nbsp;2 shows the infrared spectra of the monomers mixture, poly(PEGDA-co-AN) polymer film, poly(PEGDA-co-AN)/ LiTFSI solid electrolyte film, and Poly(PEGDA-co-AN)/LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e composite polymer film.\u003c/p\u003e\n \u003cp\u003eBy comparing their characteristic infrared absorption of the monomers mixture and the prepared copolymer, it can be found that the absorption peaks related to the C\u0026thinsp;=\u0026thinsp;C have disappeared in the copolymer, such as the peak of olefin cis\u0026thinsp;=\u0026thinsp;CH out of plane bending at 686 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, the peak of olefin trans\u0026thinsp;=\u0026thinsp;CH out of plane bending at 966 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and the peak of =\u0026thinsp;CH\u003csub\u003e2\u003c/sub\u003e at 1409 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, which indicating that the monomers take place a copolymerization. Besides, the synthesized copolymers can only show swelling in some solvents, such as acetonitrile, dimethylformamide (DMF), cyclohexane, etc. This also proves that copolymers with cross-linked structures are synthesized. For poly(PEGDA-co-AN), the peaks at 2242 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e,1728 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eand 1099 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e were also detected, which correspond to the stretching vibration characteristic peaks of -CN, -C\u0026thinsp;=\u0026thinsp;O, and C-O-C, respectively. Then, in the IR spectrum of the SPE, the peaks at 1140cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1349cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e correspond to the symmetric and asymmetric stretching vibrations of the S\u0026thinsp;=\u0026thinsp;O in LiTFSI. And the peaks at 1055 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1184 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are the stretching vibration peaks of S-N-S and C-F, respectively. For the CPE, poly(PEGDA-co-AN)/LiTFSI/nanoSiO\u003csub\u003e2\u003c/sub\u003e, the resonances peaks of Si-O-Si and O-Si-O at 468cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 808cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e can be also observed, which are characteristic peaks from SiO\u003csub\u003e2\u003c/sub\u003e nano-particle\u003csup\u003e25\u003c/sup\u003e.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv\u003e\n \u003cp\u003eThe condensed state structure of the studied samples was characterized by X-ray diffraction (XRD). The XRD curves of the cross-linked copolymer poly(PEGDA-co-AN), the SPE poly(PEGDA-co-AN)/LiTFSI and the CPE poly(PEGDA-co-AN)/LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e are shown in \u003cstrong\u003eFig.\u0026nbsp;3\u003c/strong\u003e. It can be seen that a broad peak in the range of 2\u0026theta;\u0026thinsp;=\u0026thinsp;10\u0026deg; to 30\u0026deg; is characteristic peak of incomplete crystallization (mixed phases the crystalline with amorphous regions) of poly(PEGDA-co-AN) cross-linked polymers\u003csup\u003e26, 27\u003c/sup\u003e. Moreover, after adding lithium salts, the broad XRD peak almost disappeared for the SPE and CPE indicating that the packing structure of the polymer has poor orderliness and a more complex internal structural environment, improving polymer and chain segment mobility. It is very conducive to improving the electrolyte conductivity. The crystall peak of lithium salt LiTFSI around 2\u0026theta;\u0026thinsp;=\u0026thinsp;35\u0026deg;, 40\u0026deg;and 50\u0026deg; was not observed as well \u003csup\u003e28, 29\u003c/sup\u003e, indicating that the lithium salt was well dissolved in the polymer.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\"\u003e\n \u003ch2\u003eIonic conductivity of the polymer composite electrolytes with high entropy\u003c/h2\u003e\n \u003cdiv\u003e\n \u003cp\u003eBased on our previous work\u003csup\u003e30\u003c/sup\u003e on poly(PEGDA-co-AN) copolymer electrolytes to modify its conductivity by optimizing the copolymer composition of using ternary phase diagrams, the SPE poly(PEGDA-co-AN)/LiTFSI and CPE with high-entropy poly(PEGDA-co-AN)/LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e were prepared with a molar ratio of 1:10, respectively in this paper.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eFigure\u0026nbsp;4a shows the variation curve of conductivity of SPE poly(PEGDA-co-AN) /LiTFSI system with lithium salt molar ratio. The room temperature ionic conductivity of the SPE increases with lithium salt molar ratio and reaches a maximum of 1.8 mS cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e when n\u003csub\u003ePEGDA\u003c/sub\u003e: n\u003csub\u003eAN\u003c/sub\u003e: n\u003csub\u003eLiTFSI\u003c/sub\u003e=1:10:4.2 (molar ratio). However, as the proportion of lithium salts continues to increase, their conductivity of the SPEs tends to stabilize or even slightly decrease, indicating that lithium salts have exceeded the limit solubility of polymer solvents. Figure\u0026nbsp;4b shows the variation curve of the ionic conductivity of poly(PEGDA-co-AN)/LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e CPE obtained by mixing SPE with different ratios of SiO\u003csub\u003e2\u003c/sub\u003e nanoparticle. The experimental results show that when mass fraction of SiO\u003csub\u003e2\u003c/sub\u003e added is about 5%, the CPE can reach the highest conductivity 3.51 mS cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eat 25 ℃, and then began to decrease further increasing SiO\u003csub\u003e2\u003c/sub\u003e mass fraction in CPE. This may be due to the decreased dispersion caused by excessive SiO\u003csub\u003e2\u003c/sub\u003e nanoparticles, which hinders ion transport. Figure 4c shows the conductivity of the high-entropy polymer composite electrolyte as a function of temperature fitted with VTF model.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\"\u003e\n \u003ch2\u003eLi\u003csup\u003e+\u003c/sup\u003e transport behavior in high entropy composite electrolytes\u003c/h2\u003e\n \u003cdiv\u003e\n \u003cp\u003eThe solvation of polymer for different lithium salts and the interaction between lithium ion and different ligands are quite different in an electrolyte. The transportation process of lithium ions is mainly achieved through the coordination and coordination dissociation between lithium ion and coordination atoms during the conformational relaxation of polymer chains. If the interaction between lithium ion and coordination atoms is too strong, lithium ions are not easily dissociated from coordination bonds. Conversely, the coordination force is too weak to achieve lithium ion migration in a long-rang with the thermal motion of polymer chains and their segments, as well as to dissociate from the lithium salt lattice. Therefore, there is a match between different lithium salts and the polymer structure in the electrolyte. For PEO based polymer electrolyte systems, the migration and transport of lithium ion largely depend on the effects of coordination/dissociation between lithium ion and coordinating atoms on polymer chains, as well as on the mobility of polymer PEO molecular chains and their segments. In the aforementioned XRD experimental results, there is not any diffraction peak for the SPE and CPE, confirming that the prepared electrolyte exhibited an amorphous high entropy structure. This condensed structure in electrolytes improves the mobility of polymer molecules and their segments, facilitating the migration and transport of Li\u003csup\u003e+\u003c/sup\u003e. Wang \u003cem\u003eet al\u003c/em\u003e. adopted a new approach to graft poly (vinylidene fluoride co hexafluoropropylene) chains onto polyethylene imine (PEI) with abundant -NH\u003csub\u003e2\u003c/sub\u003e groups, achieving higher modulus and conductivity\u003csup\u003e23\u003c/sup\u003e. Su \u003cem\u003eet al.\u003c/em\u003e reported a high-entropy SPE that is obtained by introducing newly designed multifunctional ABC miktoarm star terpolymers into poly(ethylene oxide), improving the Li\u003csup\u003e+\u003c/sup\u003e transference number and toughness, and inducing stable Li plating/stripping\u003csup\u003e31\u003c/sup\u003e. Hence one can see that whether Li\u003csup\u003e+\u003c/sup\u003e in the coordinated state can dissociate into free Li\u003csup\u003e+\u003c/sup\u003e in the polymer and whether free Li\u003csup\u003e+\u003c/sup\u003e can re-coordinate with other functional groups on the polymer chain or its segment is particularly important for Li\u003csup\u003e+\u003c/sup\u003e transport. Therefore, for polymer molecules with good segment mobility, efficient Li\u003csup\u003e+\u003c/sup\u003e transport can be achieved only when the coordination force and coordination dissociation force are matched between the coordinating atoms and Li\u003csup\u003e+\u003c/sup\u003e, and then enhancing the mobility of polymer molecules. Therefore, regulating the coordination/coordination dissociation between Li\u003csup\u003e+\u003c/sup\u003e and different coordinating groups are effective strategies for improving ion transport in polymer electrolytes. Figure 5 illustrates the Lewis acid-base interaction between Lewis acid SiO\u003csub\u003e2\u003c/sub\u003e particles and their adjacent polymer chains in the CPE electrolyte system. The Lewis acid-base interaction between Lewis acidic SiO\u003csub\u003e2\u003c/sub\u003e nano-particle dispersed in polymer electrolyte systems and coordination groups on polymer chains (or segments) changes the local charge environment of electrolyte polymer chains and regulates the interaction between coordination atoms and Li\u003csup\u003e+\u0026thinsp;32\u003c/sup\u003e, thereby facilitating the dissociation of Li\u003csup\u003e+\u003c/sup\u003e in the coordinated state in the electrolyte system\u003csup\u003e33\u003c/sup\u003e.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eIn the micro region without SiO\u003csub\u003e2\u003c/sub\u003e particles, the coordination force between Li\u003csup\u003e+\u003c/sup\u003e and ether oxygen atoms is stronger than that between Li\u003csup\u003e+\u003c/sup\u003e and -CN. However, at the interface between SiO\u003csub\u003e2\u003c/sub\u003e particles and polymer matrix, the Lewis acid-base interaction between SiO\u003csub\u003e2\u003c/sub\u003e and C-O is stronger than that between SiO\u003csub\u003e2\u003c/sub\u003e and -CN, resulting in the difference decreasing in coordination ability among Li\u003csup\u003e+\u003c/sup\u003e and O and N atoms, respectively. Under this effect and external electric field, once the polyether chain or the segment containing -CN takes the relaxation motion in the micro region without SiO\u003csub\u003e2\u003c/sub\u003e particles and approaches to the coordination state Li\u003csup\u003e+\u003c/sup\u003e around SiO\u003csub\u003e2\u003c/sub\u003e particles, Li\u003csup\u003e+\u003c/sup\u003e will easily undergo dissociation and re-coordination. Therefore, this effects in coordinated state lithium ions tend to occur around Lewis particles, and make the random process of Li\u003csup\u003e+\u003c/sup\u003e coordination/coordination dissociation in polymer electrolytes show the \u0026ldquo;orientation\u0026rdquo; in a certain degree.\u003c/p\u003e\n \u003cp\u003eFigure\u0026nbsp;6 shows the characteristic absorption of C-O-C and -CN stretching vibrations of the studied samples. The C-O-C and -CN stretching vibrations located at 1095 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 2241 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e respectively in the poly(PEGDA-co-AN) cross-linked polymer (without lithium salts and SiO\u003csub\u003e2\u003c/sub\u003e nano-particle). After adding SiO\u003csub\u003e2\u003c/sub\u003e nano-particle into the polymer sample, the characteristic absorption of C-O-C exhibits a red shift, shifting to 1074 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e from 1095 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; however, the stretching vibration frequency of -CN group did not show a significant change, indicating that the Lewis acid-base interaction between SiO\u003csub\u003e2\u003c/sub\u003e and the -CN group is weaker than that between SiO\u003csub\u003e2\u003c/sub\u003e and the C-O-C group. In addition, for the electrolyte samples containing lithium salt poly(PEGDA-co-AN)/LiTFSI and poly(PEGDA-co-AN)/LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e, the characteristic absorption frequencies of C-O-C and -CN were significantly higher than those in the poly Poly(PEGDA-co-AN) and Poly(PEGDA-co-AN)/SiO\u003csub\u003e2\u003c/sub\u003e samples without lithium salts, indicating that Li\u003csup\u003e+\u003c/sup\u003e acts with ether oxygen atom and with N atom of -CN respectively is also significant.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eIn order to further discuss the influence of SiO\u003csub\u003e2\u003c/sub\u003e on Li\u003csup\u003e+\u003c/sup\u003e coordination, the XPS fine spectra of C, O, and N elements in CPE and SPE were measured, as shown in Fig. 6. It can be observed from Fig. 7a that the binding energy (E\u003csub\u003eB\u003c/sub\u003e) of N1s electron shows a increase when lithium salt LiTFSI is added to the polymer to form an electrolyte. This can be attributed to the coordination effect between Li\u003csup\u003e+\u003c/sup\u003e and -CN, which leads to a stronger electron binding outside the nucleus of the N atom. As shown in Fig. 7b, the O1s E\u003csub\u003eB\u003c/sub\u003e values of C-O-C and C\u0026thinsp;=\u0026thinsp;O in the copolymer sample are different due to two kinds of chemical environment. However, for the CPE specimen the two O1s peaks corresponding to C-O and C\u0026thinsp;=\u0026thinsp;O almost overlap, and the peak assignment to C-O-C shifts towards higher binding energy, while the O1s binding energy of C\u0026thinsp;=\u0026thinsp;O decreases comparing with that in the copolymer. These results indicate that the two different oxygen atoms in C-O and C\u0026thinsp;=\u0026thinsp;O in CPEs, tend to have consistent O1s electron binding energy after being regulated by the dual effects of SiO\u003csub\u003e2\u003c/sub\u003e and lithium salts, which facilitates the dissociation of coordinated Li\u003csup\u003e+\u003c/sup\u003e on the copolymer chain. Figure 7c shows C1s fine spectrum in the peaks assignment to C-O-C and -CN related to Li\u003csup\u003e+\u003c/sup\u003e coordination become wider. This can be explained by the fact that the chemical environment of C-O-C and -CN becomes more complex after interacting with lithium salts and SiO\u003csub\u003e2\u003c/sub\u003e, and thus resulting in wider distribution in C1s binding energy in these different functional groups. The interactions among these functional groups are beneficial for their better synergistic effect in ion transport and for the improvement of conductivity.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eThe Li\u003csup\u003e+\u003c/sup\u003e transference number (t\u003csub\u003eLi+\u003c/sub\u003e) represents the proportion of lithium ion in all migrated ions, it is another important parameter that characterizes the Li\u003csup\u003e+\u003c/sup\u003e transport in electrolytes as well.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eThe Li\u003csup\u003e+\u003c/sup\u003e transference number is not only related to the ionic conductivity of the electrolyte, but also closely related to the Coulombic efficiency and charge/discharge performance of the assembled battery \u003csup\u003e34\u003c/sup\u003e. The higher the Li\u003csup\u003e+\u003c/sup\u003e transference number, the better the overall performance of the battery \u003csup\u003e35\u003c/sup\u003e. Figure\u0026nbsp;8 shows the chronoamperometry (CA) and electrochemical impedance spectrum (EIS) of the composite electrolyte. The transference number t\u003csub\u003eLi+\u003c/sub\u003e of poly(PEGDA-co-AN) /LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e CPE was calculated to be approximately 0.58 using the Bruce Vincent Evans (BVE) formula. Figure 9 shows the characteristic infrared absorption of TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e in SPE and CPE, where the characteristic absorption at 740 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e corresponds to the S-N-S stretching vibration in TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e in both electrolytes. This peak can be split into the free state TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e located at approximately 738 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and the bound state TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e located at approximately 742 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e using a software\u003csup\u003e36\u003c/sup\u003e. By comparing the split areas of TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e peaks, it can be found that the peak area of bound TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e in CPE is larger than that in the SPE. This is due to the Lewis acid-base interaction between Lewis acid SiO\u003csub\u003e2\u003c/sub\u003e and TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e, which is capable to inhibiting TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e movement in the electrolyte under an external electric field. Based on this, it can be seen that the Lewis acid-base interaction between uniformly dispersed nano SiO\u003csub\u003e2\u003c/sub\u003e particles and TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e is beneficial for improving the Li\u003csup\u003e+\u003c/sup\u003e transference number.\u003c/p\u003e\n \u003cp\u003eThe analysis based on XRD, FT-IR, and XPS results suggests that SiO\u003csub\u003e2\u003c/sub\u003e in composite polymer electrolytes not only contributes to the high entropy properties of the system, inhibits the crystallization of PEO segments, improves the mobility of polymer segments, but also regulates the local charge environment between polymer molecules and their segments. Through Lewis acid-base interactions, the coordination and dissociation abilities in the composite electrolyte system are also regulated between lithium ions and the polymer coordination groups, such as -CN, C-O-C and C\u0026thinsp;=\u0026thinsp;O etc. This effect improves the conductivity of the electrolyte, and SiO\u003csub\u003e2\u003c/sub\u003e can inhibit the migration of lithium salt anions in the electrolyte, ultimately improving the Li\u003csup\u003e+\u003c/sup\u003e transport ability of the electrolyte.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\"\u003e\n \u003ch2\u003eStability of high entropy composite polymer electrolytes\u003c/h2\u003e\n \u003cdiv\u003e\n \u003cp\u003eThe thermal stability and electrochemical stability of the electrolyte directly affects the safety of battery usage. The thermal stability of these studied samples was characterized by TGA and their TGA curves are shown in Fig.\u0026nbsp;10.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eIt can be found that their thermal decomposition temperatures are more than 300 ℃ for both the polymer and the electrolyte. The electrochemical stability was characterized by linear cyclic voltammetry (CV) scanning technology to determine the electrochemical stability window of the electrolyte. Figure\u0026nbsp;11 shows the CV scanning curves of a lithium stainless steel half cell assembled with poly (PEGDA-co-AN)/LiTFSI SPE and Poly (PEGDA-co-AN)/LiTFSI/SiO\u003csub\u003e2\u003c/sub\u003e CPE, respectively.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eThe CPE exhibits good electrochemical stability, and without significant redox peaks below 5 V. The wide electrochemical stability window of the electrolyte can be attributed to the introduction of AN monomers with high dielectric constants in polymer structure. The highly polar -CN in the polymer effectively reduces the electron density of its adjacent ester group (COO\u003csup\u003e\u0026minus;\u003c/sup\u003e) and improves overall oxidation resistance. On the other hand, the withdrawing electron effect from -CN can suppress the frontier orbital electron from concentrating on the ester group but also distributes on AN segments\u003csup\u003e37\u003c/sup\u003e. Delocalization of frontier electrons is helpful for avoiding an oxidation reaction to take place on a certain position. In adding, that TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e anion is bounded by SiO\u003csub\u003e2\u003c/sub\u003e reduces the decomposition of anionic TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e near the electrode, resulting in better electrochemical stability of the electrolyte.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003ePolymers with high dielectric constants have a strong solvation action on lithium salts. The ether oxygen atoms in PEO polymers have strong coordination with alkali metal lithium ion, but for PEO-based polymers their chains relaxation is difficult due to high crystallinity at room temperature; PAN has high electrochemical and thermal stability, good mechanical and processing properties, as well as good flame retardancy.\u003c/p\u003e \u003cp\u003eIn this paper, a crossing-linked copolymer poly(PEGDA-co-AN) and its composite polymer electrolyte poly(PEGDA-co-AN)/LiTFSI/nano-SiO\u003csub\u003e2\u003c/sub\u003e with a high entropy structure and high conductivity were designed and prepared. The structures of the copolymers and the key indexes of the composite polymer electrolytes were characterized, respectively. The Lewis acid-base interactions of -CN and C-O with nano SiO\u003csub\u003e2\u003c/sub\u003e in the polymer electrolyte system and the actions on the behavior of Li\u003csup\u003e+\u003c/sup\u003e coordination/coordination dissociation were studied using XRD, FT-IR, and XPS. It is believed that the Lewis acid-base interaction of SiO\u003csub\u003e2\u003c/sub\u003e nano-particles with ether-oxygen atoms and -CN groups in the copolymer reduces the strong coordination force between Li\u003csup\u003e+\u003c/sup\u003e and ether-oxygen atoms, and leads to the averaging effect of Li\u003csup\u003e+\u003c/sup\u003e coordination with -CN and C-O, respectively. In addition, Lewis acid nano-SiO\u003csub\u003e2\u003c/sub\u003e also inhibits the migration of lithium anion TFSI\u003csup\u003e\u0026minus;\u003c/sup\u003e under an external electric field. A new strategy was proposed to improve the lithium ion transport performance in composite polymer electrolytes by adding appropriate amount of SiO\u003csub\u003e2\u003c/sub\u003e nano-particle to regulate the local charge environment of the polymer in poly (PEGDA-co-AN) /LiTFSI electrolyte system, and a high entropy structure composite polymer electrolyte, poly (PEGDA-co-AN) /LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e, was successfully fabricated which has a high room temperature ionic conductivity of 3.5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e S cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, Li\u003csup\u003e+\u003c/sup\u003e transference number of 0.58, and an electrochemical window greater than 5 V.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eConfict of interest The authors declare that they have no conficts of interest related to the content of this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eACKNOWLEDGMENTS\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank Professor Zou Qichao in Hubei University who assisted in thermal analysis, and Zhang Guohong, PhD in Test \u0026amp; Analysis Central of Wuhan University of Science and Technology who assisted in XPS, XRD, and FT-IR test.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYF.Z conducted major experiments and characterization content, prepared all the images and wrote the article manuscript; X.W participated in sample preparation and contributed to the data collection and analysis ; S.PJ was responsible for the overall planning, design and implementation of the study, and supervised and coordinated the entire study.All authors reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003eNo datasets were generated or analysed during the current study.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCheng X-B, Zhang R, Zhao C-Z, Zhang Q. 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Advanced Materials. 2022;35. http://dx.doi.org/10.1002/adma.202110423\u003c/li\u003e\n\u003cli\u003eZhaoxiang Wang, Biying Huang, Rongjian Xue, Xuejie Huang, Chen* L. Spectroscopic investigation of interactions among components and ion transport mechanism in polyacrylonitrile based electrolytes. Solid State Ionics. 1999;121: 141-156. http://dx.doi.org/10.1016/s0167-2738(98)00541-4\u003c/li\u003e\n\u003cli\u003eZhu J, Zhang Z, Zhao S, Westover AS, Belharouak I, Cao PF. Single‐Ion Conducting Polymer Electrolytes for Solid‐State Lithium\u0026ndash;Metal Batteries: Design, Performance, and Challenges. Advanced Energy Materials. 2021;11. http://dx.doi.org/10.1002/aenm.202003836\u003c/li\u003e\n\u003cli\u003eMeng N, Ye Y, Yang Z, Li H, Lian F. Developing Single‐Ion Conductive Polymer Electrolytes for High‐Energy‐Density Solid State Batteries. Advanced Functional Materials. 2023;33. http://dx.doi.org/10.1002/adfm.202305072\u003c/li\u003e\n\u003cli\u003eLiu K, Cheng H, Wang Z, et al. A 3 \u0026micro;m‐Ultrathin Hybrid Electrolyte Membrane with Integrative Architecture for All‐Solid‐State Lithium Metal Batteries. Advanced Energy Materials. 2024;14. http://dx.doi.org/10.1002/aenm.202303940\u003c/li\u003e\n\u003cli\u003eTang L, Chen B, Zhang Z, et al. Polyfluorinated crosslinker-based solid polymer electrolytes for long-cycling 4.5\u0026thinsp;V lithium metal batteries. Nature Communications. 2023;14. http://dx.doi.org/10.1038/s41467-023-37997-6\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"polymer-bulletin","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pobu","sideBox":"Learn more about [Polymer Bulletin](http://link.springer.com/journal/289)","snPcode":"289","submissionUrl":"https://submission.nature.com/new-submission/289/3","title":"Polymer Bulletin","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"High entropy electrolytes, Polymer composite electrolytes, Lewis acid-base interactions, Li+ transport, All solid state lithium batteries","lastPublishedDoi":"10.21203/rs.3.rs-4682986/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4682986/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eUsing solid electrolytes instead of traditional liquid electrolytes to assemble all solid state batteries can effectively solve the problem of electrolyte leakage and reduce risks caused by lithium dendrite growth during charging and discharging processes, which is capable to improving the safety of lithium battery. Solid polymer electrolytes have been widely studied in consideration of the factors, such as flexible structural design, convenient preparation, low cost, good interface contact with electrodes, and ease of large-scale production. Polyethylene oxide (PEO) polymers have a good salvation for most lithium salts, but PEO segments in polymers have high crystallinity at room temperature and a narrow Electrochemical Stability Window (ESW), which will limit some advanced electrode materials with high potential used in batteries and restricts the improvement of battery performance as well. Polyacrylonitrile (PAN) with high dielectric constant has high electrochemical and thermal stability, good mechanical processing properties, and excellent fire retardancy. In this manuscript, a cross-linked copolymer, poly (PEGDA-co-AN) is prepared using Polyethylene glycol diacrylate (PEGDA) and Acrylonitrile (AN) as monomers and 2,2-Azobisisobutyronitrile (AIBN) as a thermal initiator; the influence of Lewis acid-base interaction between nano SiO\u003csub\u003e2\u003c/sub\u003e additive and -C≡N or C-O-C on Li\u003csup\u003e+\u003c/sup\u003e transport has been investigated, and a new idea was proposed to improve the lithium ion transport in poly (PEGDA-co-AN) based polymer composite electrolytes by adjusting the local charge environment of polymer electrolytes. Finally, a composite polymer electrolyte poly (PEGDA-co-AN)/LiTFSI/nano SiO\u003csub\u003e2\u003c/sub\u003e with high entropy structure and high conductivity has been designed and fabricated, and it exhibits a room temperature ionic conductivity of 3.5×10\u003csup\u003e−3\u003c/sup\u003e S cm\u003csup\u003e−1\u003c/sup\u003e, Li\u003csup\u003e+\u003c/sup\u003e transference number of 0.58, and the electrochemical stability window greater than 5 V.\u003c/p\u003e","manuscriptTitle":"A solid composite electrolyte poly(PEGDA-co-AN)/ LiTFSI/nano SiO2 with high conductivity and high entropy structure and its Li+ transport behavior","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-29 11:01:11","doi":"10.21203/rs.3.rs-4682986/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-08-27T07:33:33+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-08-24T09:48:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"276783055482985755084894360573428229054","date":"2024-08-12T06:52:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-08-12T06:38:22+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-07-05T14:59:49+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-07-04T13:42:50+00:00","index":"","fulltext":""},{"type":"submitted","content":"Polymer Bulletin","date":"2024-07-04T00:43:32+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"polymer-bulletin","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pobu","sideBox":"Learn more about [Polymer Bulletin](http://link.springer.com/journal/289)","snPcode":"289","submissionUrl":"https://submission.nature.com/new-submission/289/3","title":"Polymer Bulletin","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"84ac548d-da5a-4a00-b702-4651f093455c","owner":[],"postedDate":"July 29th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-10-21T16:00:46+00:00","versionOfRecord":{"articleIdentity":"rs-4682986","link":"https://doi.org/10.1007/s00289-024-05540-2","journal":{"identity":"polymer-bulletin","isVorOnly":false,"title":"Polymer Bulletin"},"publishedOn":"2024-10-15 15:56:55","publishedOnDateReadable":"October 15th, 2024"},"versionCreatedAt":"2024-07-29 11:01:11","video":"","vorDoi":"10.1007/s00289-024-05540-2","vorDoiUrl":"https://doi.org/10.1007/s00289-024-05540-2","workflowStages":[]},"version":"v1","identity":"rs-4682986","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4682986","identity":"rs-4682986","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}