Investigations on structural and electrical properties of ZnO based nanoparticles and composite

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R. Rathod, Mehul Parmar, Himanshu Dadhich, N. A. Chondagar, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5797355/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Diluted magnetic semiconductors (DMS) have emerged as promising candidates for spintronic devices, offering a unique combination of semiconducting and magnetic properties. In the present study, ZnO (Z) and Zn 0.2 Cu 0.8 O (C) nanostructured materials were synthesized using sol–gel and co–precipitation methods, respectively. Their composite, ZnO: Zn 0.2 Cu 0.8 O (ZC), was fabricated to investigate the structural and electrical properties. X–ray diffraction (XRD) analysis confirms the hexagonal wurtzite phase and reveals a reduced crystallite size and suppressed lattice strain across the lattice of ZC composite, as compared to the pure phases (i.e. Z & C). Rietveld refinements and Williamson–Hall (W–H) analysis further established changes in lattice parameters and strain effect. The dielectric constant, measured for a frequency range between 20 Hz and 2 MHz, shows a significant enhancement in its values for composite material which can be attributed to the interfacial polarization and oxygen vacancies. Impedance spectroscopy reveals lower impedance in the ZC composite indicating better conduction pathways due to enhanced defect density and grain boundary interactions. AC conductivity, analyzed using Jonscher's power law, demonstrates that the correlated barrier hopping (CBH) mechanism governs the conduction, with ZC composite sample exhibiting the highest conductivity among all the three samples. These findings suggest that the composite exhibits improved dielectric and electrical performance due to synergistic effects between ZnO and Zn 0.2 Cu 0.8 O phases, making it a promising material for electronic and optoelectronic applications. Structural properties Electrical properties Sol–Gel Co–precipitation ZnO Nanoparticles Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Introduction In diluted magnetic semiconductors (DMS), a fraction of the host cation elements can be replaced by transition metal or rare earth ions. Scientists and researchers are highly interested due to their potential applications in spintronics devices since they exploit the intrinsic spins of the charge carriers in addition to their fundamental electric charge [ 1 ]. Among the various oxide–based semiconductors such as CuO, TiO 2 , SnO 2 and ZnO [ 2 – 5 ], nanostructured ZnO is multifunctional material with coexistence of magnetic, semiconducting, electrical and optical properties [ 2 , 5 – 7 ]. ZnO has a wide direct band gap of ~ 3.37 eV and high excitation binding energy of ~ 60 meV at room temperature. In this context, it can be used in optoelectronic devices in visible range [ 8 – 10 ]. For transition metal doped nanostructured ZnO, structural and electrical properties have been reported [ 11 , 12 ]. Several research articles are available on the studies on Cu–doped zinc oxide nanostructured materials prepared using various methods, such as the co–precipitation method [ 13 ], the solid–state method [ 14 ] and the wet chemical method [ 15 ]. ZnO is known for its variety of applications in biosensor, antimicrobial activity and photo catalytic activities [ 16 ]. In addition, the capability of the materials in different applications can be tailored by either doping or composite or both. Vagadia et al [ 17 ] have prepared ZnO with 5% and 15% Co doping levels using sol–gel method and solid–state reaction method which has identified that microstructure and synthesis method modify the magnetic behaviour of Co doped ZnO. Joshi et al [ 18 ] have investigated various electrical properties of sol–gel grown ZnO nanoparticles including frequency dependent real permittivity, ac conductivity and impedance. All these properties have been discussed on the basis of oxygen vacancies created with different sintering temperatures. Zankat et al [ 19 ] have performed structural and electrical studies for the ZnO: Zn 0.95 Al 0.05 O matrix composites, prepared with ZnO nano fillers and ZnAlO as matrix using low–cost sol–gel and solid–state reaction method, respectively. All the electrical properties such as frequency dependent dielectric, conductivity and impedance have been discussed on the basis of the nanofiller used in the composite materials. Sajjad et al [ 20 ] have prepared pure and Cu doped zinc oxide using co–precipitation method for identifying the effect of copper doping on optical band gap of ZnO nanoparticles. Zn 0.2 Cu 0.8 O is a ternary oxide compound, where a specific proportion of zinc (Zn) is substituted into the copper oxide (CuO) lattice. This material exhibits unique electrical and optical properties due to the combined effects of Cu and Zn, making it an interesting subject of study for various applications in electronics and optoelectronics. In this compound, Cu and Zn elements contribute to different functionalities. Copper, with its variable oxidation states, introduces p–type conductivity and influences the compound's band structure. Zinc, when incorporated into the CuO lattice, modifies the crystal structure, potentially enhancing the materials electrical and optical characteristics. The precise stoichiometry of Zn 0.2 Cu 0.8 O allows for the exploration of synergetic effects that are not present in the individual oxides [ 21 – 25 ]. Considering the diverse electrical behaviors of various dopants in ZnO, potential ZnO–based composites, and their intriguing electrical properties, this study has been focused on the synthesis of ZnO: Zn 0.2 Cu 0.8 O nano–composites. ZnO was synthesized via an eco–friendly and cost–effective sol–gel method utilizing an acetate precursor, while Zn 0.2 Cu 0.8 O was prepared through a co–precipitation method using citric acid. The primary objective of these composites is to establish a distinct interface and investigate modifications in electrical properties relative to pure ZnO. Experimental details Nanoparticles of ZnO and Zn 0.2 Cu 0.8 O were successfully synthesized by employing cost effective sol–gel technique. For ZnO nanoparticles, zinc acetate dihydrate (Zn (CH 3 COO) 2 ·2H 2 O) (make: Sigma–Aldrich; purity: 99.99%) was stirred in ethanol for 1h using magnetic stirrer. To obtain precipitates from the solution, the mixture was kept on the hot plate for 48 h. Obtained precipitates were heated at 120 ℃ for 90 min and then again heated at 200 ℃ for 90 min. The obtained powder was then calcined for 4 h at 500 ℃. For synthesis of Zn 0.2 Cu 0.8 O nanoparticles, copper (II) sulphate (CuSO 4 ) (make: Sigma–Aldrich; purity: 99.99%) and zinc (II) acetate solution was hybridized with citric acid (C 6 H 8 O 7 ) (make: Sigma–Aldrich; purity: 99.99%) to form a homogeneous solution. Then 10 ml of 1 M NaOH solution was mixed drop by drop and stirred for 1 h. This solution was again kept for 48 h to form better form of precipitates. The obtained precipitates were washed with distilled water to remove the presence of extra ions and impurity. After washing the precipitates were heated at 170 ℃ for 6 h to get a brownish–black powder of Zn 0.2 Cu 0.8 O. To remove organic impurities from the materials, the powder was then calcined at 500 ℃ for 4 h. To make composite from both pure ZnO and Cu doped ZnO nanolattices, both materials were mixed together in 1:1 ratio with proper grinding process for 15 min. All materials were pressed in the pellets form and sintered at 600 ℃ for 4 h. For the sake of simplicity, from now, ZnO, Zn 0.8 Cu 0.2 O, and ZnO: Zn 0.8 Cu 0.2 O will be denoted as Z, C, and ZC, respectively. To study the structural properties, X–ray diffraction (XRD) measurement was performed at room temperature using Cu Kα X–ray source in X–ray diffractometer (make: Philips; model: PW 3040/60 X’pert PRO), the range of 2θ was kept between 20° to 80° for pure ZnO (Z), pure Zn 0.2 Cu 0.8 O (C) and composite of ZnO: Zn 0.8 Cu 0.2 O (ZC) samples. XRD patterns were refined and analysed by performing Rietveld refinements using FULLPROF code. To understand the electrical properties, frequency dependent dielectric constant (ε’), ac conductivity (σ) and impedance (Z) measurements for Z, C and ZC samples were performed in the frequency range of 20 Hz to 2 MHz using LCR meter (make: Agilent; model: E4980A). Results and discussion In order to confirm the single phase nature of ZnO (Z), Zn 0.2 Cu 0.8 O (C) and their composite ZnO: Zn 0.2 Cu 0.8 O (ZC) composites, XRD measurement was performed for the 2θ range of 20˚–80˚, as shown in Fig. 1 . Figure 1 shows the single phase nature without any detectable impurities (other than ZnO and Zn 0.2 Cu 0.8 O phases) within the measurement range. All the samples show hexagonal wurtzite unit cell structure with the set of (hkl) parameters indexed in Fig. 1 by considering JCPDS no 36–1451 for Z and JCPDS no 05–0661 for C nanoparticles [ 26 ]. To estimate crystallite size, scherrer’s formula [crystallite size (CS) = 0.9 λ/B cosθ] was employed for present Z and C. It is found that Z nanoparticles possess an average crystallite size of ~ 32.30 nm and C nanoparticles possess an average crystallite size of ~ 20.38 nm. The intensity of specific peaks corresponding to individual nanoparticles is diminished in the composite sample, which can be attributed to a decrease in the crystallinity of the samples. It is clear from the inset that, upon the mixing of Zn 0.2 Cu 0.8 O nanoparticles with ZnO nanoparticles, the XRD peaks get shifted towards higher 2θ angle suggesting a reduction in the lattice parameters and cell volume. Figure 2 shows the Rietveld refined XRD patterns of pure and composite of Z and C materials studied. All the XRD patterns were fitted with FULLPROF code [ 27 ] clearly indicating that all the three samples possess hexagonal wurtzite structure with P63mc space group symmetry. Lattice parameters obtained from refinements are listed in Table 1 for all the three samples (i.e. Z, C & ZC). It is noticeable from Table 1 that the lattice parameters of Z in ZC composite get slightly changed however lattice parameters of C material get changed in the composite which can modify the nature of composite. For C, slight changes in lattice parameters are observed in the composite, which might be due to interactions or stress effects in the composite material. Overall, the analysis suggests that the composite structure is well–refined, demonstrating an almost stable crystalline phase for phase Z, whereas phase C exhibits slight lattice adjustments attributable to the formation of the composite. Figure 3 shows the W–H plots with linear fitting for ZnO (Z), Zn 0.2 Cu 0.8 O (C) and ZC composite samples. Williamson and Hall proposed a method, known as W–H plots, for obtaining size and strain broadening by considering peak width as a function of 2θ. The plot of β cosθ on y–axis and 4 sinθ on x–axis with linear fit gives lattice strain. The slope from the straight line provides value of intrinsic lattice strain and intercept provides average crystallite size [ 28 , 29 ]. Relation between crystallite size and strain can be expressed as: β hkl cosθ = (Kλ/D) + 4ε sinθ, where β hkl = FWHM of Bragg peaks, θ = angle of peak position, λ = wavelengths of the X–rays (1.5406 Å), D = average crystallite size, ε = lattice strain and K = Scherrer’s constant (K = 0.9 for the present case). At present, it is necessary to highlight here that XRD patterns of Z and C samples have few peaks those get merged with each other (specifically at higher angles) therefore crystallite size calculations have been done for various possible phases as follows: crystallite size of ZnO nanoparticles is found to be ~ 33.55 nm from W–H plots while the crystallite size of ZnO in composite on excluding the merged peaks is ~ 35.26 nm whereas if including the merged peaks, it is found to be ~ 28.22 nm. The crystallite size of pure C nanoparticles is ~ 27.77 nm. In composite the crystallite size of C nanoparticles is ~ 26.15 nm excluding merged peaks and ~ 19.09 nm including the merged peaks. Hence, it can be stated that crystallite size is found to be reduced for ZC composite. The reduction in crystallite size in the composite, particularly when considering merged peaks, suggests increased strain and interaction effects between the ZnO and Zn 0.2 Cu 0.8 O phases. This indicates a more complex crystallographic environment in the composite, likely due to interfacial stresses and potential phase interactions. The most intense (101) and (111) peaks of XRD patterns of Z nanoparticles and C nanoparticles, respectively, have been considered in scherrer’s formula while all the peak contributions have been involved in the estimation of an average crystallite size for W–H plots. Which becomes the reason to have smaller values of crystallites for the case of W–H plots as compared to corresponding scherrer’s formula [ 30 , 31 ]. Figure 4 shows the graph of texture coefficients against reflection of pure Z and C samples. The degree of preferred orientations of the different crystalline planes can be determined using Harris method for calculating the texture coefficients, by equation, T C (hkl) = n (I (hkl) /I 0 (hkl) )/Σ (I (hkl) /I 0 (hkl) ) where, T C (hkl) is the texture coefficient, I (hkl) is the measured intensity of the peak (hkl) , I 0 (hkl) is the relative intensity of the corresponding peak from a powder XRD reference and n is the number of peaks. Higher the value of texture coefficient supports the larger number of grains arranged in the same orientation. T C (hkl) equals to 1 suggests the equiaxed sample based on the material’s database structure whereas higher values of T C (hkl) indicate the complete preferred orientations in that particular (hkl) plane. From Fig. 4 , one can state that (200) plane possesses the higher texture coefficient therefore higher crystalline orientation within this (200) plane can be realized for ZnO nanoparticles where as Zn 0.2 Cu 0.8 O nanoparticles possess maximum crystalline orientations toward (021) crystalline plane. In addition, Zn 0.2 Cu 0.8 O nanoparticles have better orientations toward various crystalline planes. Figure 5 shows the dielectric constant (ε’) vs frequency (f) recorded at room temperature for pure and composite of Z and C nanoparticles. All the samples show higher values of dielectric constant at lower values of frequency that decreases with increase in frequency due to higher relaxation time at lower frequencies [ 32 ]. Behaviour of dielectric constant with frequency can be understood in terms of relaxation of dipole, at lower frequencies, dipoles can easily relax with applied frequency. At higher frequencies, it is difficult to align with frequency therefore it gives high and low dielectric constant, respectively. The changes in dielectric response can be explained by Koop’s theory which explains the dielectric nature of materials by assuming the dielectric as a Maxwell–Wagner (M–W) inhomogeneous type medium consisting of high resistive grains and low resistive grain boundaries within the lattices of Z, C & ZC [ 33 ]. Pure Z nanoparticles show the lower dielectric constant as compared to pure C nanoparticles which can be attributed to the Cu–O bonds in the structure of C samples where these Cu–O bonds are non–collinear and can be easily align with changing applied electric field (i.e. frequency) thereby, exhibiting large dielectric constant by Zn 0.2 Cu 0.8 O (C). For the composite material, the values of dielectric constant are higher than Z nanoparticles and lower than C nanoparticles. In case of composite C, nanoparticles are mixed with Z nanoparticles which have small crystallite size compared to Z nanoparticles. As a consequence, a large number of possible oxygen vacancies gets created which supports the space charge polarization within the composite sample (better than Z sample) because of that composite shows higher dielectric constant than Z nanoparticles. Both the nanoparticles were mixed in the same amount in composite, however the contribution of C nanoparticles with the number of Cu–O bonds get suppressed to dielectric constant thereby composite exhibits smaller dielectric constant than C samples. To understand the relaxation process involved in the present case of pure and composite materials understudy, the obtained dielectric response have theoretically been fitted using the cole–cole relaxation formula: ε′ = ε ∞ + [(ε S – ε ∞ )/{1 + (j fτ) (1–α) }] in Fig. 5 , where ε ∞ and ε S are the high frequency and static dielectric constants, respectively, τ is the relaxation time and α is the parameter estimating the distribution of relaxation time for the pure and composite samples understudy. Values of α should always vary between 0 and 1 for any oxide samples. As shown in Fig. 5 , all the curves are nicely fitted with the mentioned relaxation formula for the dielectric responses throughout the frequency range studied. Obtained value of τ is found to be ~ 30 µs and ~ 0.16 µs for pure Z and C nanomaterials whereas for composite, value of τ is found to be ~ 7.14 µs which shows that Z nanoparticles take more time to relax with applied ac electric field which can be correlated with lower values of dielectric constant for Z nanoparticles. Values of α obtained from the relaxation fittings are found to be ~ 0.12, 0.57 and 0.77 for Z, ZC and C nanomaterials which can be correlated with the larger dielectric constant observed for ZC composite material compared to Z & C nanoparticles. Electrical polarizable nature, effectively governed by the boundaries between the crystals across the nanostructured lattices in the presently studied pure and composite samples of Z and C samples, can also be understood on the basis of (i) Maxwell–Wagner interfacial polarization [ 34 , 35 ], (ii) Koop’s theory of dielectric [ 36 ] and (iii) universal dielectric response (UDR) [ 37 ]. Generally, UDR model is best for those systems which consist of coexisting low high resistive microstructural regions. Figure 6 shows the plots of log (ε’f) vs log (f) for Z, C and ZC composite materials with linear fits throughout the frequency range studied. Linear fits suggest that the dielectric behaviours of all three pure and composite samples follow the UDR model that simultaneously accounts for the high resistive crystals of, both ZnO (Z) and Zn 0.2 Cu 0.8 O (C) as well as low resistance boundaries of Z and C nanostructured lattices. Figure 7 shows the frequency dependent impedance of the samples with logarithmic scale and enlarged view of the frequency range between 1 and 1.5 MHz. Impedance of the samples decreases with increase of frequency for all the samples. Upon application of electric field, the free charge carriers get excited across the lattices. This provides the conduction and suppression of the impedance [ 28 ]. One can realize from Fig. 9 that C sample exhibits highest impedance (as compared to pure Z & ZC composite) throughout the frequency range studied. This can be understood as : Zn 0.2 Cu 0.8 O (C) sample experience two different mechanisms, namely, (i) C sample across its lattice thereby there exists size mismatch between existing cations that results in the structure disorder experience hurdles to cross the lattice that results in the higher impedance, as compared to Z and ZC samples and (ii) C sample possesses lower crystallite size therefore it possesses large number of crystallite boundaries and, hence, free charge carriers get enhanced in numbers that support the conduction and reduction in impedance can be expects. However, mechanism (ii) is overcome by the mechanism (i) that supports the larger impedance exhibited by C sample as compared to other two nanostructured oxides. For the (a) C of ZC composite, one can expect the opposite condition where mechanism (ii) is dominating over the mechanism (i) since mixture of the two (i.e. Z & C) activates the more defects and imperfection across the lattice of ZC sample thereby impedance can be expected lower than Z & C samples. Here, it is necessary to highlight that Z and C combination in ZC composite is mainly based on physical interaction across their boundaries without any chemical mixing or incorporation of Cu or Zn ions within their grains or crystallites. Figure 8 shows the variation in ac conductivity with frequency (range between 20 Hz and 2 MHz) for all the three samples. The ac conductivity behaviors have been theoretically fitted using Jonscher’s power law for all three samples. Conventionally, it is observed that ac conductivity increases with increase in frequency throughout the frequency range studied for all three samples. This can be ascribed to the energy gained by charge carriers at higher frequencies. In the present case of nanocomposite sample (ZC), conductivity gets improved as compared to other samples pure Z & C throughout the frequency range studied. This can be understood as: Observed largest ac conductivity for ZC composite can be understood on the basis of crystallite size where upon combination of Z & C nanoparticles (to form the ZC composite), the crystallite size of both, ZnO & Zn 0.2 Cu 0.8 O, pure oxide nanoparticles get suppressed effectively thereby provide larger numbers of crystallite boundaries where crystallite boundaries support the charge carrier density to the electrical transport across the ZC lattice and, hence, ac conductivity can be realized largest for ZC composite among the three samples understudy. Generally, ac conductivity can be the representation of inverse or opposite to impedance values with respect to any external parameters. However, for the present case of ac conductivity for pure Z and pure C nanoparticles, one can realize higher ac conductivity for pure C samples (besides its highest impedance among the three studied samples) as compared to Z pure nanoparticles. This can be ascribed to the effect of smaller crystallite size of C thereby C possesses larger number of crystallite boundaries having larger number of free carriers that support the conduction across the lattice of C nanoparticles as compared to pure Z nanoparticles. The ac conductivity at different frequencies fitted for all the three samples using Jonscher’s power law calculated from equation: σ ac (f) = σ dc + A × f η , where, σ ac is derived conductivity A is materials specific temperature dependent constant, σ dc is conductivity at zero frequency, f is frequency and η is power exponent. For ac conductivity, mechanism is mainly based on the value of power exponent η, there has been only two possible cases: (i) when η > 1 then lattice conduction is controlled by Maxwell–Wagner (W–M) relaxation mechanism and (ii) 0 < η < 1 then lattice conduction is believed to governed by the correlated barrier hopping (CBH) mechanism [ 38 , 39 ]. It is observed that power law has been fitted properly for all the three samples. Table 2 shows the maximum barrier height W m and power exponent η of pure and composite materials. The value of power exponent η for pure Z nanoparticles is found to be ~ 0.17 and for pure C nanoparticles it is found to be ~ 0.53, however further enhanced η for ZC composites ~ 0.76 can be realized from the fitting. The values of power exponent η can be found less than one (η < 1) for all three samples which indicates that for all the three samples, ac conductivity is governed by the CBH mechanism. One can also estimate the values of maximum barrier height from the obtained values of power exponent η for all the nanostructured samples by using the equation: η = 1–(6k b T/W m ), where k b is Boltzmann constant in eV/K, T is the employed temperature (i.e. 300K for the present case) and W m is the maximum barrier height which is required to provide the conduction across the lattices of pure and composite nanostructured oxide systems understudy. Estimated values of W m are found to be ~ 186.87 meV for Z nanoparticles which gets enhanced for C nanoparticles up to 330.01 meV from the Table 2 . This can be attributed to the role of internal structural disorder across the Zn 0.2 Cu 0.8 O nanoparticles (due to cationic size mismatch effect). For the ZC composite sample, W m is found to be highest ~ 646.28 meV among all the three samples. Which can be ascribed to the effect of mixing (of Z & C nanoparticles) based created defect and imperfection across the crystallite boundaries regions. These regions provide the hurdles to the movements of change carriers across the ZC lattice therefore ZC samples exhibit the highest value of maximum barrier height as compared to pure Z & C nanoparticles. Conclusion In conclusion, we have successfully synthesized ZnO (Z), Zn 0.2 Cu 0.8 O (C) and ZnO: Zn 0.2 Cu 0.8 O (ZC) composite nanoparticles where both individual nanoparticles were synthesized using sol–gel method and co-precipitation technique, respectively, whereas composite was prepared by mixing of two nanomaterials in the same ratio. XRD analysis confirms the stability of the hexagonal wurtzite phase for all samples, with noticeable strain effects and a reduction in crystallite size in the composite. Dielectric studies reveal that the ZC composite exhibits a higher dielectric constant compared to pure ZnO due to increased polarization effects at the interface and oxygen vacancies. The dielectric response was well–fitted using the cole–cole relaxation model, yielding relaxation time of ~ 30 µs for Z, ~ 0.16 µs for C and ~ 7.14 µs for ZC. The values of parameter α indicate broader relaxation time distribution for C and ZC samples, correlating with higher dielectric values. Impedance analysis demonstrates that all samples exhibit decreasing impedance with increasing frequency, attributed to the activation of free charge carriers. The C sample exhibits the highest impedance across the frequency range, likely due to lattice disorder caused by cation size mismatches, which created barriers for charge carrier movements. In contrast, the ZC composite exhibits lower impedance than pure Z and C samples. This reduction arises from the formation of additional defects and grain boundaries at the interfaces between Z and C crystallites in ZC sample, which facilitates the charge carrier transport. AC conductivity measurements confirm the CBH mechanism as the dominant conduction process, with the ZC composite showing the highest conductivity across the studied frequency range. Declarations Declaration of interest statement The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article. Data availability All the data recorded and analyzed during the present investigations are included in this published article. Competing Interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article Author Contribution I testify on behalf of all co-authors that our article submitted to Journal of Sol Gel Science and Technology:Title: Investigations on structural and electrical properties of ZnO based nanoparticles and compositeAll authors: V.R. Rathod, Mehul Parmar, Himanshu Dadhich, N.A. Chondagar, Khushal Sagapariya, Uday Kareleeya, R.K. Trivedi, P.P. Bardapurkar, Karan Rathod, S.B. Kansara, N.A. Shah, P.S. Solanki..(1) This material has not been published in whole or in part elsewhere.(2) The manuscript is not currently being considered for publication in another journal.(3) All authors have been personally and actively involved in substantive work leading to the manuscript, and will hold themselves jointly and individually responsible for its content. Acknowledgement Corresponding author Himanshu Dadhich is thankful to all coauthors for supporting this article. References S.A. Wolf, D.D. Awschalom, R.A. Buhrman, J.M. Daughton, S. Von Molnar, M.L. Roukes, A.Y. Chtchelkanova, D.M. Treger, Spintronic: A spin–based electronics vision for the future, Science 294 (2001) 1488–1495. M.V. Kanani, Davit Dhruv, H.K. Rathod, K.N. Rathod, Bhargav Rajyaguru, A.D. Joshi, P.S. Solanki, N.A. Shah, D.D. 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Appl. Phys. 98 (2005) 041301. P.P. Subha, M.K. Jayaraj, Enhanced room temperature gas sensing properties of low temperature solution processed ZnO/CuO heterojunction. BMC Chemistry 13 (2019) 4. T. Shahid, M. Arfan, W. Ahmad; T. BiBi, T. Muhammad Khan, Synthesis and Doping Feasibility of Composite–hydroxide–mediated Approach for The Cu 1–x Zn x O Nanomaterials. Adv. Mater. Lett. 7 (2016) 561–566. M.Y. El Sayed, N. E. Ghouch, G.O. Younes, R. Awad, Structural, morphological, and magneto–optical investigations of pure and (Sn, Zn) Co–doped CuO nanoparticles: A novel corrosion inhibitor in acidic media, Mater. Today Commun. 35 (2023) 105490. N Widiarti, J.K. Sae, S. Wahyuni, Synthesis CuO–ZnO nanocomposite and its application as an antibacterial agent, IOP Conf. Ser.: Mater. Sci. Eng. 172 (2017) 012036–012047. J. Rodriguez Carvajal, FULLPROF version 3.0 Laboratorie Leon Brillioun, CEA–CNRS, (1995). Urvashi Jambukiya, Mayur Parmar, Neeta A. Bhammar, K.N. Rathod, Debashish Sarkar, M.R. Gonal, Davit Dhruv, P.S. Solanki, D.D. Pandya, N.A. Shah, A.D. Joshi, Investigation on various properties of Dy 0.7 Ca 0.3 MnO 3 : TiO 2 based nano–micro composites, J. Alloys Comp. 967 (2023) 171532. Prachi Desai, Vaishnavi Darji, M.P. Deshpande, S.H. Chaki, Pinkesh G. Sutariya, Heni Soni, P.S. Solanki, N.A. Shah, Bharavi Hirpara, Dielectric performance of nanostructured magnesium oxide and effect of cobalt substitution Mater. Today Commun. 38 (2024) 108022. V.D. Mote, Y. Purushotham, B.N. Dole, Williamson–Hall analysis in estimation of lattice strain in nanometer–sized ZnO particles, J. Theor. Appl. Phys. 6 (2012) 6:1–8. A. Khorsand Zak, W.H. Abd. Majid, M.E. Abrishami, Raminyousefi, X–ray analysis of ZnO nanoparticles by Williamson–Hall and size–strain plot methods Solid State Sci. 13 (2011) 251–256. M.S. Samuel, J. Koshy, A. Chandran, K.C. George, Dielectric behavior and transport properties of ZnO nanorods, Phys. B 406 (2011) 3023–3029. C.G. Koops, On the dispersion of resistivity and dielectric constant of some semiconductors at audio frequencies, Phys. Rev. 83 (1951) 121–124. P.V. Reddy, T.S. Rao, Dielectric behaviour of mixed Li–Ni ferrites at low frequencies, J. Less Common. Met. 86 (1982) 255–261. Mayur Lagariya, Mansi Modi, Himanshu Dadhich, Manan Gal, Keval Gadani, P.S. Solanki, N. A. Shah, Studies on structural and electrical behaviors of chemically grown ZnO/SnO 2 nanocomposites, Physica B Condens. Matte. 577 (2020) 411774. C.G. Koops, On the dispersion of resistivity and dielectric constant of some semiconductors at audio frequencies, Phys. Rev. B, 83 (1951) 121–124. D.V. Efremov, J.V.D. Brink, D.I. Khomskii, Bond–versus site–centred ordering and possible ferroelectricity in manganites, Nat. Mater. 3 (2004) 853–856. Naisargi Kanabar, Keval Gadani, V. G. Shrimali, Khushal Sagapariya, K. N. Rathod, Bhagyashree Udeshi, Joyce Joseph, D.D. Pandya, P.S. Solanki1, N. A. Shah, Structural and electrical properties of sol–gel grown nanostructured ZnO and LaMnO 3 particle–based nanocomposites, Appl. Phys. A 127 (2021) 122–133. Drashti Sanghvi, Hetal Boricha, Bharavi Hirpara, Sapana Solanki, V. G. Shrimali, A. D. Joshi, P. S. Solanki, N. A. Shah, Sintering temperature dependent electrical properties of sol–gel grown nanostructured Bi 0.95 Nd 0.05 FeO 3 multiferroics, J. Sol–Gel Sci. Technol.93 (2020) 666–677. Tables Table 1 Rietveld refined parameters for Z, C and ZC composite samples. Parameters ZnO (Z) Zn 0.2 Cu 0.8 O (C) ZC Composite ZnO (Z) Zn 0.2 Cu 0.8 O (C) a(Å) 3.2491 4.6793 3.2490 4.6916 b(Å) 3.2491 3.4239 3.2490 3.4304 c(Å) 5.2051 5.1294 5.2048 5.1204 R F 3.517 9.762 4.2561 8.1822 R Bragg 3.771 10.68 2.8590 5.2406 R WP 19.10 24.50 20.00 R exp 12.96 16.71 15.25 R P 15.30 30.90 21.80 χ 2 2.18 2.15 1.72 Table 2 Maximum barrier height (W m ) and Power exponent (η) calculated Jonscher’s power law formula for all three samples. Sample code Power Exponent (η) Maximum Barrier Height (W m in MeV) Z (ZnO) 0.17 189.87 C (Zn 0.2 Cu 0.8 O) 0.53 330.01 ZC (ZnO: Zn 0.2 Cu 0.8 O) 0.76 646.28 Additional Declarations Competing interest reported. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-5797355","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":400072689,"identity":"fd0b5b1e-8d1d-4f75-a8c8-6acf3c4f1a55","order_by":0,"name":"V. R. Rathod","email":"","orcid":"","institution":"H.\u0026 H.B. Kotak Institute of Science","correspondingAuthor":false,"prefix":"","firstName":"V.","middleName":"R.","lastName":"Rathod","suffix":""},{"id":400072690,"identity":"7d678961-bce5-4bd8-9908-dd52d8e84a7c","order_by":1,"name":"Mehul Parmar","email":"","orcid":"","institution":"Saurashtra University","correspondingAuthor":false,"prefix":"","firstName":"Mehul","middleName":"","lastName":"Parmar","suffix":""},{"id":400072691,"identity":"91da4b24-668f-4384-8532-b21a475f4b9d","order_by":2,"name":"Himanshu Dadhich","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFUlEQVRIiWNgGAWjYBACA2YwdQCEzBgSGA4ws7E3gMQtiNfCzsdzACQugVsLA7IWIMkvJ5EAEsGtxZydO/FzwZ87iX3HD2978KDmjjSb5POrG34USDDwt3cnYNNi2cy7WXpm27PEmWfSyg0Sjj0zZpPOKbvZA3SYxJmzG7A67DDvBmnehsOJGw7kmEkkNhxOBmpJu8ED1GIgkYtLy+bfPH+AWs6/AWupb5M8k3bzD34t26R52IBabkBsYWaTYD92m4At26x52w4bz7zxrEwi4RhQC08O220ZAwkenH45f3bzbaDDZPvOJ2+T/FFzmFm+/fizm2/+2Mjxt/di1YIN8IAji4dY5SDA/oAU1aNgFIyCUTD8AQBcfmzIAuD8WgAAAABJRU5ErkJggg==","orcid":"","institution":"Vivekananda Global University","correspondingAuthor":true,"prefix":"","firstName":"Himanshu","middleName":"","lastName":"Dadhich","suffix":""},{"id":400072692,"identity":"a433eac6-77ca-40df-9ace-7c2b26b4a983","order_by":3,"name":"N. A. Chondagar","email":"","orcid":"","institution":"Saurashtra University","correspondingAuthor":false,"prefix":"","firstName":"N.","middleName":"A.","lastName":"Chondagar","suffix":""},{"id":400072694,"identity":"5c9b56dd-b1fb-4fbd-956d-803a2b4f2930","order_by":4,"name":"Khushal Sagapariya","email":"","orcid":"","institution":"Darshan University","correspondingAuthor":false,"prefix":"","firstName":"Khushal","middleName":"","lastName":"Sagapariya","suffix":""},{"id":400072696,"identity":"365dce60-252c-47ae-b03e-cf70b030388c","order_by":5,"name":"Uday Kareleeya","email":"","orcid":"","institution":"Saurashtra University","correspondingAuthor":false,"prefix":"","firstName":"Uday","middleName":"","lastName":"Kareleeya","suffix":""},{"id":400072697,"identity":"d4a7e64a-f796-4758-82bc-86fcd08dc6cc","order_by":6,"name":"R. K. Trivedi","email":"","orcid":"","institution":"H.\u0026 H.B. Kotak Institute of Science","correspondingAuthor":false,"prefix":"","firstName":"R.","middleName":"K.","lastName":"Trivedi","suffix":""},{"id":400072698,"identity":"bab31c33-8a03-4f7d-aa56-d751bc537eba","order_by":7,"name":"P. P. Bardapurkar","email":"","orcid":"","institution":"S.N. Arts, D.J. Malpani Commerce \u0026 B.N. Sarda Science College","correspondingAuthor":false,"prefix":"","firstName":"P.","middleName":"P.","lastName":"Bardapurkar","suffix":""},{"id":400072699,"identity":"adea3a19-9bac-4ec5-9677-4eb4ae2e4375","order_by":8,"name":"Karan Rathod","email":"","orcid":"","institution":"RK University","correspondingAuthor":false,"prefix":"","firstName":"Karan","middleName":"","lastName":"Rathod","suffix":""},{"id":400072700,"identity":"904ed66b-3473-4d2b-9c7f-5e76a383049a","order_by":9,"name":"S. B. Kansara","email":"","orcid":"","institution":"Shri. P.H.G. Muni. Arts \u0026 Science College","correspondingAuthor":false,"prefix":"","firstName":"S.","middleName":"B.","lastName":"Kansara","suffix":""},{"id":400072701,"identity":"b8c3a74f-02cf-4b5f-ba7f-18012b12f2cb","order_by":10,"name":"N. A. Shah","email":"","orcid":"","institution":"Saurashtra University","correspondingAuthor":false,"prefix":"","firstName":"N.","middleName":"A.","lastName":"Shah","suffix":""},{"id":400072702,"identity":"104e8aac-7e42-44a7-b4fb-8482ffcaeaa9","order_by":11,"name":"P. S. Solanki","email":"","orcid":"","institution":"Saurashtra University","correspondingAuthor":false,"prefix":"","firstName":"P.","middleName":"S.","lastName":"Solanki","suffix":""}],"badges":[],"createdAt":"2025-01-09 14:38:30","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5797355/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5797355/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":73645308,"identity":"d6da697d-bd48-492c-a39e-a8ffa8bb5461","added_by":"auto","created_at":"2025-01-13 08:51:18","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":241881,"visible":true,"origin":"","legend":"\u003cp\u003eXRD patterns with 2θ range: 20˚ ̶ 80˚ and Inset: enlarged view for 2θ: 30˚ ̶ 40˚ collected for comparison of peak shifting.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/add0a73886d2e20ac7a789c8.png"},{"id":73645295,"identity":"e79e730a-ef61-4acb-a45f-4aab489493de","added_by":"auto","created_at":"2025-01-13 08:51:17","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":205232,"visible":true,"origin":"","legend":"\u003cp\u003eRietveld refinement of XRD patterns for Z, C and ZC samples.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/2460669addc88cfaa255b2ff.png"},{"id":73646961,"identity":"11e6f56a-9976-421b-9e54-0a519d813b49","added_by":"auto","created_at":"2025-01-13 08:59:18","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":418487,"visible":true,"origin":"","legend":"\u003cp\u003eW–H plots of Z, C and ZC composite samples (a) Pure Z nanoparticles (b) ZC composite with ZnO major and merged peaks excluded (c) ZC composite with Z major and merged peaks included (d) Pure C nanoparticles (e) ZC composite with C major and merged peaks excluded (f) ZC composite with C major and merged peaks included.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/211735ec4ac6c6218fee64cd.png"},{"id":73646952,"identity":"f0a14e48-c35e-4ad7-bf8f-038993f10843","added_by":"auto","created_at":"2025-01-13 08:59:17","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":363667,"visible":true,"origin":"","legend":"\u003cp\u003eTexture coefficient analysis of (a) Z nanoparticles and (b) C nanoparticles\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/a9d22b5ab15d4eff5e4c7261.png"},{"id":73645319,"identity":"969a5d36-9554-4442-a348-a0863c7532ff","added_by":"auto","created_at":"2025-01-13 08:51:18","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":138509,"visible":true,"origin":"","legend":"\u003cp\u003eFrequency dependent dielectric constant for Z nanoparticles, C nanoparticles and ZC composite samples. fitting lines were generated by employing cole cole relaxation formula.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/ece528c88c152fa10919453d.png"},{"id":73645303,"identity":"c5e1816c-795d-487b-b46e-7e35299d505d","added_by":"auto","created_at":"2025-01-13 08:51:17","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":124808,"visible":true,"origin":"","legend":"\u003cp\u003ePlots of log (ε′f) vs log (f) for Z, C and ZC composite samples with linear fits\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/2dd6f55d951d807969a4434e.png"},{"id":73646954,"identity":"aa10cdfb-2305-4f85-95aa-771f259403ce","added_by":"auto","created_at":"2025-01-13 08:59:17","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":335183,"visible":true,"origin":"","legend":"\u003cp\u003eFrequency dependent impedance for Z, C and ZC composite samples.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/4f741a9f162ea604ecd5d893.png"},{"id":73645305,"identity":"8b3853cc-a264-47d1-8821-e510a232be2f","added_by":"auto","created_at":"2025-01-13 08:51:18","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":149235,"visible":true,"origin":"","legend":"\u003cp\u003evariation in ac conductivity with frequency for Z, C and ZC composite samples. Fitting lines were generated by employing Jonscher’s power law formula.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/6df42fb53754e0ce38163d5e.png"},{"id":74218549,"identity":"3c7cf7c6-8fc7-49bd-aea1-697a182bd035","added_by":"auto","created_at":"2025-01-20 06:09:32","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2116734,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5797355/v1/517aede2-7825-492b-a3c5-4d72c62b22cb.pdf"}],"financialInterests":"Competing interest reported. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article","formattedTitle":"Investigations on structural and electrical properties of ZnO based nanoparticles and composite","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn diluted magnetic semiconductors (DMS), a fraction of the host cation elements can be replaced by transition metal or rare earth ions. Scientists and researchers are highly interested due to their potential applications in spintronics devices since they exploit the intrinsic spins of the charge carriers in addition to their fundamental electric charge [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Among the various oxide\u0026ndash;based semiconductors such as CuO, TiO\u003csub\u003e2\u003c/sub\u003e, SnO\u003csub\u003e2\u003c/sub\u003e and ZnO [\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], nanostructured ZnO is multifunctional material with coexistence of magnetic, semiconducting, electrical and optical properties [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. ZnO has a wide direct band gap of ~\u0026thinsp;3.37 eV and high excitation binding energy of ~\u0026thinsp;60 meV at room temperature. In this context, it can be used in optoelectronic devices in visible range [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. For transition metal doped nanostructured ZnO, structural and electrical properties have been reported [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Several research articles are available on the studies on Cu\u0026ndash;doped zinc oxide nanostructured materials prepared using various methods, such as the co\u0026ndash;precipitation method [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], the solid\u0026ndash;state method [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] and the wet chemical method [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eZnO is known for its variety of applications in biosensor, antimicrobial activity and photo catalytic activities [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In addition, the capability of the materials in different applications can be tailored by either doping or composite or both. Vagadia et al [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] have prepared ZnO with 5% and 15% Co doping levels using sol\u0026ndash;gel method and solid\u0026ndash;state reaction method which has identified that microstructure and synthesis method modify the magnetic behaviour of Co doped ZnO. Joshi et al [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] have investigated various electrical properties of sol\u0026ndash;gel grown ZnO nanoparticles including frequency dependent real permittivity, ac conductivity and impedance. All these properties have been discussed on the basis of oxygen vacancies created with different sintering temperatures. Zankat et al [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] have performed structural and electrical studies for the ZnO: Zn\u003csub\u003e0.95\u003c/sub\u003eAl\u003csub\u003e0.05\u003c/sub\u003eO matrix composites, prepared with ZnO nano fillers and ZnAlO as matrix using low\u0026ndash;cost sol\u0026ndash;gel and solid\u0026ndash;state reaction method, respectively. All the electrical properties such as frequency dependent dielectric, conductivity and impedance have been discussed on the basis of the nanofiller used in the composite materials. Sajjad et al [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] have prepared pure and Cu doped zinc oxide using co\u0026ndash;precipitation method for identifying the effect of copper doping on optical band gap of ZnO nanoparticles.\u003c/p\u003e \u003cp\u003eZn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO is a ternary oxide compound, where a specific proportion of zinc (Zn) is substituted into the copper oxide (CuO) lattice. This material exhibits unique electrical and optical properties due to the combined effects of Cu and Zn, making it an interesting subject of study for various applications in electronics and optoelectronics. In this compound, Cu and Zn elements contribute to different functionalities. Copper, with its variable oxidation states, introduces p\u0026ndash;type conductivity and influences the compound's band structure. Zinc, when incorporated into the CuO lattice, modifies the crystal structure, potentially enhancing the materials electrical and optical characteristics. The precise stoichiometry of Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO allows for the exploration of synergetic effects that are not present in the individual oxides [\u003cspan additionalcitationids=\"CR22 CR23 CR24\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eConsidering the diverse electrical behaviors of various dopants in ZnO, potential ZnO\u0026ndash;based composites, and their intriguing electrical properties, this study has been focused on the synthesis of ZnO: Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nano\u0026ndash;composites. ZnO was synthesized via an eco\u0026ndash;friendly and cost\u0026ndash;effective sol\u0026ndash;gel method utilizing an acetate precursor, while Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO was prepared through a co\u0026ndash;precipitation method using citric acid. The primary objective of these composites is to establish a distinct interface and investigate modifications in electrical properties relative to pure ZnO.\u003c/p\u003e"},{"header":"Experimental details","content":"\u003cp\u003eNanoparticles of ZnO and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO were successfully synthesized by employing cost effective sol\u0026ndash;gel technique. For ZnO nanoparticles, zinc acetate dihydrate (Zn (CH\u003csub\u003e3\u003c/sub\u003eCOO)\u003csub\u003e2\u003c/sub\u003e\u0026middot;2H\u003csub\u003e2\u003c/sub\u003eO) (make: Sigma\u0026ndash;Aldrich; purity: 99.99%) was stirred in ethanol for 1h using magnetic stirrer. To obtain precipitates from the solution, the mixture was kept on the hot plate for 48 h. Obtained precipitates were heated at 120 ℃ for 90 min and then again heated at 200 ℃ for 90 min. The obtained powder was then calcined for 4 h at 500 ℃. For synthesis of Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nanoparticles, copper (II) sulphate (CuSO\u003csub\u003e4\u003c/sub\u003e) (make: Sigma\u0026ndash;Aldrich; purity: 99.99%) and zinc (II) acetate solution was hybridized with citric acid (C\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e8\u003c/sub\u003eO\u003csub\u003e7\u003c/sub\u003e) (make: Sigma\u0026ndash;Aldrich; purity: 99.99%) to form a homogeneous solution. Then 10 ml of 1 M NaOH solution was mixed drop by drop and stirred for 1 h. This solution was again kept for 48 h to form better form of precipitates. The obtained precipitates were washed with distilled water to remove the presence of extra ions and impurity. After washing the precipitates were heated at 170 ℃ for 6 h to get a brownish\u0026ndash;black powder of Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO. To remove organic impurities from the materials, the powder was then calcined at 500 ℃ for 4 h. To make composite from both pure ZnO and Cu doped ZnO nanolattices, both materials were mixed together in 1:1 ratio with proper grinding process for 15 min. All materials were pressed in the pellets form and sintered at 600 ℃ for 4 h. For the sake of simplicity, from now, ZnO, Zn\u003csub\u003e0.8\u003c/sub\u003eCu\u003csub\u003e0.2\u003c/sub\u003eO, and ZnO: Zn\u003csub\u003e0.8\u003c/sub\u003eCu\u003csub\u003e0.2\u003c/sub\u003eO will be denoted as Z, C, and ZC, respectively. To study the structural properties, X\u0026ndash;ray diffraction (XRD) measurement was performed at room temperature using Cu Kα X\u0026ndash;ray source in X\u0026ndash;ray diffractometer (make: Philips; model: PW 3040/60 X\u0026rsquo;pert PRO), the range of 2θ was kept between 20\u0026deg; to 80\u0026deg; for pure ZnO (Z), pure Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) and composite of ZnO: Zn\u003csub\u003e0.8\u003c/sub\u003eCu\u003csub\u003e0.2\u003c/sub\u003eO (ZC) samples. XRD patterns were refined and analysed by performing Rietveld refinements using FULLPROF code. To understand the electrical properties, frequency dependent dielectric constant (ε\u0026rsquo;), ac conductivity (σ) and impedance (Z) measurements for Z, C and ZC samples were performed in the frequency range of 20 Hz to 2 MHz using LCR meter (make: Agilent; model: E4980A).\u003c/p\u003e"},{"header":"Results and discussion","content":"\u003cp\u003eIn order to confirm the single phase nature of ZnO (Z), Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) and their composite ZnO: Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (ZC) composites, XRD measurement was performed for the 2θ range of 20˚\u0026ndash;80˚, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the single phase nature without any detectable impurities (other than ZnO and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO phases) within the measurement range. All the samples show hexagonal wurtzite unit cell structure with the set of \u003cem\u003e(hkl)\u003c/em\u003e parameters indexed in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e by considering JCPDS no 36\u0026ndash;1451 for Z and JCPDS no 05\u0026ndash;0661 for C nanoparticles [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. To estimate crystallite size, scherrer\u0026rsquo;s formula [crystallite size (CS)\u0026thinsp;=\u0026thinsp;0.9 λ/B cosθ] was employed for present Z and C. It is found that Z nanoparticles possess an average crystallite size of ~\u0026thinsp;32.30 nm and C nanoparticles possess an average crystallite size of ~\u0026thinsp;20.38 nm. The intensity of specific peaks corresponding to individual nanoparticles is diminished in the composite sample, which can be attributed to a decrease in the crystallinity of the samples. It is clear from the inset that, upon the mixing of Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nanoparticles with ZnO nanoparticles, the XRD peaks get shifted towards higher 2θ angle suggesting a reduction in the lattice parameters and cell volume.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the Rietveld refined XRD patterns of pure and composite of Z and C materials studied. All the XRD patterns were fitted with FULLPROF code [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] clearly indicating that all the three samples possess hexagonal wurtzite structure with \u003cem\u003eP63mc\u003c/em\u003e space group symmetry. Lattice parameters obtained from refinements are listed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e for all the three samples (i.e. Z, C \u0026amp; ZC). It is noticeable from Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e that the lattice parameters of Z in ZC composite get slightly changed however lattice parameters of C material get changed in the composite which can modify the nature of composite. For C, slight changes in lattice parameters are observed in the composite, which might be due to interactions or stress effects in the composite material. Overall, the analysis suggests that the composite structure is well\u0026ndash;refined, demonstrating an almost stable crystalline phase for phase Z, whereas phase C exhibits slight lattice adjustments attributable to the formation of the composite.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows the W\u0026ndash;H plots with linear fitting for ZnO (Z), Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) and ZC composite samples. Williamson and Hall proposed a method, known as W\u0026ndash;H plots, for obtaining size and strain broadening by considering peak width as a function of 2θ. The plot of β cosθ on y\u0026ndash;axis and 4 sinθ on x\u0026ndash;axis with linear fit gives lattice strain. The slope from the straight line provides value of intrinsic lattice strain and intercept provides average crystallite size [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Relation between crystallite size and strain can be expressed as: β\u003csub\u003ehkl\u003c/sub\u003e cosθ = (Kλ/D)\u0026thinsp;+\u0026thinsp;4ε sinθ, where β\u003csub\u003ehkl\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;FWHM of Bragg peaks, θ\u0026thinsp;=\u0026thinsp;angle of peak position, λ\u0026thinsp;=\u0026thinsp;wavelengths of the X\u0026ndash;rays (1.5406 \u0026Aring;), D\u0026thinsp;=\u0026thinsp;average crystallite size, ε\u0026thinsp;=\u0026thinsp;lattice strain and K\u0026thinsp;=\u0026thinsp;Scherrer\u0026rsquo;s constant (K\u0026thinsp;=\u0026thinsp;0.9 for the present case). At present, it is necessary to highlight here that XRD patterns of Z and C samples have few peaks those get merged with each other (specifically at higher angles) therefore crystallite size calculations have been done for various possible phases as follows: crystallite size of ZnO nanoparticles is found to be ~\u0026thinsp;33.55 nm from W\u0026ndash;H plots while the crystallite size of ZnO in composite on excluding the merged peaks is ~\u0026thinsp;35.26 nm whereas if including the merged peaks, it is found to be ~\u0026thinsp;28.22 nm. The crystallite size of pure C nanoparticles is ~\u0026thinsp;27.77 nm. In composite the crystallite size of C nanoparticles is ~\u0026thinsp;26.15 nm excluding merged peaks and ~\u0026thinsp;19.09 nm including the merged peaks. Hence, it can be stated that crystallite size is found to be reduced for ZC composite. The reduction in crystallite size in the composite, particularly when considering merged peaks, suggests increased strain and interaction effects between the ZnO and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO phases. This indicates a more complex crystallographic environment in the composite, likely due to interfacial stresses and potential phase interactions. The most intense \u003cem\u003e(101)\u003c/em\u003e and \u003cem\u003e(111)\u003c/em\u003e peaks of XRD patterns of Z nanoparticles and C nanoparticles, respectively, have been considered in scherrer\u0026rsquo;s formula while all the peak contributions have been involved in the estimation of an average crystallite size for W\u0026ndash;H plots. Which becomes the reason to have smaller values of crystallites for the case of W\u0026ndash;H plots as compared to corresponding scherrer\u0026rsquo;s formula [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows the graph of texture coefficients against reflection of pure Z and C samples. The degree of preferred orientations of the different crystalline planes can be determined using Harris method for calculating the texture coefficients, by equation, T\u003csub\u003eC\u003c/sub\u003e \u003cem\u003e(hkl)\u003c/em\u003e\u0026thinsp;=\u0026thinsp;n (I\u003csub\u003e\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e/I\u003csub\u003e0\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e)/Σ (I\u003csub\u003e\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e/I\u003csub\u003e0\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e) where, T\u003csub\u003eC\u003c/sub\u003e \u003cem\u003e(hkl)\u003c/em\u003e is the texture coefficient, I\u003csub\u003e\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e is the measured intensity of the peak \u003cem\u003e(hkl)\u003c/em\u003e, I\u003csub\u003e0\u003cem\u003e(hkl)\u003c/em\u003e\u003c/sub\u003e is the relative intensity of the corresponding peak from a powder XRD reference and n is the number of peaks. Higher the value of texture coefficient supports the larger number of grains arranged in the same orientation. T\u003csub\u003eC\u003c/sub\u003e \u003cem\u003e(hkl)\u003c/em\u003e equals to 1 suggests the equiaxed sample based on the material\u0026rsquo;s database structure whereas higher values of T\u003csub\u003eC\u003c/sub\u003e \u003cem\u003e(hkl)\u003c/em\u003e indicate the complete preferred orientations in that particular \u003cem\u003e(hkl)\u003c/em\u003e plane. From Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003e, one can state that \u003cem\u003e(200)\u003c/em\u003e plane possesses the higher texture coefficient therefore higher crystalline orientation within this \u003cem\u003e(200)\u003c/em\u003e plane can be realized for ZnO nanoparticles where as Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nanoparticles possess maximum crystalline orientations toward \u003cem\u003e(021)\u003c/em\u003e crystalline plane. In addition, Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nanoparticles have better orientations toward various crystalline planes.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows the dielectric constant (ε\u0026rsquo;) vs frequency (f) recorded at room temperature for pure and composite of Z and C nanoparticles. All the samples show higher values of dielectric constant at lower values of frequency that decreases with increase in frequency due to higher relaxation time at lower frequencies [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Behaviour of dielectric constant with frequency can be understood in terms of relaxation of dipole, at lower frequencies, dipoles can easily relax with applied frequency. At higher frequencies, it is difficult to align with frequency therefore it gives high and low dielectric constant, respectively. The changes in dielectric response can be explained by Koop\u0026rsquo;s theory which explains the dielectric nature of materials by assuming the dielectric as a Maxwell\u0026ndash;Wagner (M\u0026ndash;W) inhomogeneous type medium consisting of high resistive grains and low resistive grain boundaries within the lattices of Z, C \u0026amp; ZC [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Pure Z nanoparticles show the lower dielectric constant as compared to pure C nanoparticles which can be attributed to the Cu\u0026ndash;O bonds in the structure of C samples where these Cu\u0026ndash;O bonds are non\u0026ndash;collinear and can be easily align with changing applied electric field (i.e. frequency) thereby, exhibiting large dielectric constant by Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C). For the composite material, the values of dielectric constant are higher than Z nanoparticles and lower than C nanoparticles. In case of composite C, nanoparticles are mixed with Z nanoparticles which have small crystallite size compared to Z nanoparticles. As a consequence, a large number of possible oxygen vacancies gets created which supports the space charge polarization within the composite sample (better than Z sample) because of that composite shows higher dielectric constant than Z nanoparticles. Both the nanoparticles were mixed in the same amount in composite, however the contribution of C nanoparticles with the number of Cu\u0026ndash;O bonds get suppressed to dielectric constant thereby composite exhibits smaller dielectric constant than C samples.\u003c/p\u003e \u003cp\u003eTo understand the relaxation process involved in the present case of pure and composite materials understudy, the obtained dielectric response have theoretically been fitted using the cole\u0026ndash;cole relaxation formula: ε\u0026prime; = ε\u003csub\u003e\u0026infin;\u003c/sub\u003e+ [(ε\u003csub\u003eS\u003c/sub\u003e\u0026ndash; ε\u003csub\u003e\u0026infin;\u003c/sub\u003e)/{1 + (j fτ)\u003csup\u003e(1\u0026ndash;α)\u003c/sup\u003e}] in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e5\u003c/span\u003e, where ε\u003csub\u003e\u0026infin;\u003c/sub\u003e and ε\u003csub\u003eS\u003c/sub\u003e are the high frequency and static dielectric constants, respectively, τ is the relaxation time and α is the parameter estimating the distribution of relaxation time for the pure and composite samples understudy. Values of α should always vary between 0 and 1 for any oxide samples. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e5\u003c/span\u003e, all the curves are nicely fitted with the mentioned relaxation formula for the dielectric responses throughout the frequency range studied. Obtained value of τ is found to be ~\u0026thinsp;30 \u0026micro;s and ~\u0026thinsp;0.16 \u0026micro;s for pure Z and C nanomaterials whereas for composite, value of τ is found to be ~\u0026thinsp;7.14 \u0026micro;s which shows that Z nanoparticles take more time to relax with applied ac electric field which can be correlated with lower values of dielectric constant for Z nanoparticles. Values of α obtained from the relaxation fittings are found to be ~\u0026thinsp;0.12, 0.57 and 0.77 for Z, ZC and C nanomaterials which can be correlated with the larger dielectric constant observed for ZC composite material compared to Z \u0026amp; C nanoparticles.\u003c/p\u003e \u003cp\u003eElectrical polarizable nature, effectively governed by the boundaries between the crystals across the nanostructured lattices in the presently studied pure and composite samples of Z and C samples, can also be understood on the basis of (i) Maxwell\u0026ndash;Wagner interfacial polarization [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e], (ii) Koop\u0026rsquo;s theory of dielectric [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] and (iii) universal dielectric response (UDR) [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. Generally, UDR model is best for those systems which consist of coexisting low high resistive microstructural regions. Figure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e6\u003c/span\u003e shows the plots of log (ε\u0026rsquo;f) vs log (f) for Z, C and ZC composite materials with linear fits throughout the frequency range studied. Linear fits suggest that the dielectric behaviours of all three pure and composite samples follow the UDR model that simultaneously accounts for the high resistive crystals of, both ZnO (Z) and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) as well as low resistance boundaries of Z and C nanostructured lattices.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e7\u003c/span\u003e shows the frequency dependent impedance of the samples with logarithmic scale and enlarged view of the frequency range between 1 and 1.5 MHz. Impedance of the samples decreases with increase of frequency for all the samples. Upon application of electric field, the free charge carriers get excited across the lattices. This provides the conduction and suppression of the impedance [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. One can realize from Fig.\u0026nbsp;9 that C sample exhibits highest impedance (as compared to pure Z \u0026amp; ZC composite) throughout the frequency range studied. This can be understood as : Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) sample experience two different mechanisms, namely, (i) C sample across its lattice thereby there exists size mismatch between existing cations that results in the structure disorder experience hurdles to cross the lattice that results in the higher impedance, as compared to Z and ZC samples and (ii) C sample possesses lower crystallite size therefore it possesses large number of crystallite boundaries and, hence, free charge carriers get enhanced in numbers that support the conduction and reduction in impedance can be expects. However, mechanism (ii) is overcome by the mechanism (i) that supports the larger impedance exhibited by C sample as compared to other two nanostructured oxides. For the (a) C of ZC composite, one can expect the opposite condition where mechanism (ii) is dominating over the mechanism (i) since mixture of the two (i.e. Z \u0026amp; C) activates the more defects and imperfection across the lattice of ZC sample thereby impedance can be expected lower than Z \u0026amp; C samples. Here, it is necessary to highlight that Z and C combination in ZC composite is mainly based on physical interaction across their boundaries without any chemical mixing or incorporation of Cu or Zn ions within their grains or crystallites.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e8\u003c/span\u003e shows the variation in ac conductivity with frequency (range between 20 Hz and 2 MHz) for all the three samples. The ac conductivity behaviors have been theoretically fitted using Jonscher\u0026rsquo;s power law for all three samples. Conventionally, it is observed that ac conductivity increases with increase in frequency throughout the frequency range studied for all three samples. This can be ascribed to the energy gained by charge carriers at higher frequencies. In the present case of nanocomposite sample (ZC), conductivity gets improved as compared to other samples pure Z \u0026amp; C throughout the frequency range studied. This can be understood as: Observed largest ac conductivity for ZC composite can be understood on the basis of crystallite size where upon combination of Z \u0026amp; C nanoparticles (to form the ZC composite), the crystallite size of both, ZnO \u0026amp; Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO, pure oxide nanoparticles get suppressed effectively thereby provide larger numbers of crystallite boundaries where crystallite boundaries support the charge carrier density to the electrical transport across the ZC lattice and, hence, ac conductivity can be realized largest for ZC composite among the three samples understudy. Generally, ac conductivity can be the representation of inverse or opposite to impedance values with respect to any external parameters. However, for the present case of ac conductivity for pure Z and pure C nanoparticles, one can realize higher ac conductivity for pure C samples (besides its highest impedance among the three studied samples) as compared to Z pure nanoparticles. This can be ascribed to the effect of smaller crystallite size of C thereby C possesses larger number of crystallite boundaries having larger number of free carriers that support the conduction across the lattice of C nanoparticles as compared to pure Z nanoparticles. The ac conductivity at different frequencies fitted for all the three samples using Jonscher\u0026rsquo;s power law calculated from equation: σ\u003csub\u003eac\u003c/sub\u003e(f) = σ\u003csub\u003edc\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;A \u0026times; f \u003csup\u003eη\u003c/sup\u003e, where, σ\u003csub\u003eac\u003c/sub\u003e is derived conductivity A is materials specific temperature dependent constant, σ \u003csub\u003edc\u003c/sub\u003e is conductivity at zero frequency, f is frequency and η is power exponent. For ac conductivity, mechanism is mainly based on the value of power exponent η, there has been only two possible cases: (i) when η\u0026thinsp;\u0026gt;\u0026thinsp;1 then lattice conduction is controlled by Maxwell\u0026ndash;Wagner (W\u0026ndash;M) relaxation mechanism and (ii) 0\u0026thinsp;\u0026lt;\u0026thinsp;η\u0026thinsp;\u0026lt;\u0026thinsp;1 then lattice conduction is believed to governed by the correlated barrier hopping (CBH) mechanism [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. It is observed that power law has been fitted properly for all the three samples. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the maximum barrier height W\u003csub\u003em\u003c/sub\u003e and power exponent η of pure and composite materials. The value of power exponent η for pure Z nanoparticles is found to be ~\u0026thinsp;0.17 and for pure C nanoparticles it is found to be ~\u0026thinsp;0.53, however further enhanced η for ZC composites\u0026thinsp;~\u0026thinsp;0.76 can be realized from the fitting. The values of power exponent η can be found less than one (η\u0026thinsp;\u0026lt;\u0026thinsp;1) for all three samples which indicates that for all the three samples, ac conductivity is governed by the CBH mechanism. One can also estimate the values of maximum barrier height from the obtained values of power exponent η for all the nanostructured samples by using the equation: η\u0026thinsp;=\u0026thinsp;1\u0026ndash;(6k\u003csub\u003eb\u003c/sub\u003eT/W\u003csub\u003em\u003c/sub\u003e), where k\u003csub\u003eb\u003c/sub\u003e is Boltzmann constant in eV/K, T is the employed temperature (i.e. 300K for the present case) and W\u003csub\u003em\u003c/sub\u003e is the maximum barrier height which is required to provide the conduction across the lattices of pure and composite nanostructured oxide systems understudy. Estimated values of W\u003csub\u003em\u003c/sub\u003e are found to be ~\u0026thinsp;186.87 meV for Z nanoparticles which gets enhanced for C nanoparticles up to 330.01 meV from the Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. This can be attributed to the role of internal structural disorder across the Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO nanoparticles (due to cationic size mismatch effect). For the ZC composite sample, W\u003csub\u003em\u003c/sub\u003e is found to be highest\u0026thinsp;~\u0026thinsp;646.28 meV among all the three samples. Which can be ascribed to the effect of mixing (of Z \u0026amp; C nanoparticles) based created defect and imperfection across the crystallite boundaries regions. These regions provide the hurdles to the movements of change carriers across the ZC lattice therefore ZC samples exhibit the highest value of maximum barrier height as compared to pure Z \u0026amp; C nanoparticles.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, we have successfully synthesized ZnO (Z), Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) and ZnO: Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (ZC) composite nanoparticles where both individual nanoparticles were synthesized using sol\u0026ndash;gel method and co-precipitation technique, respectively, whereas composite was prepared by mixing of two nanomaterials in the same ratio. XRD analysis confirms the stability of the hexagonal wurtzite phase for all samples, with noticeable strain effects and a reduction in crystallite size in the composite. Dielectric studies reveal that the ZC composite exhibits a higher dielectric constant compared to pure ZnO due to increased polarization effects at the interface and oxygen vacancies. The dielectric response was well\u0026ndash;fitted using the cole\u0026ndash;cole relaxation model, yielding relaxation time of ~\u0026thinsp;30 \u0026micro;s for Z, ~ 0.16 \u0026micro;s for C and ~\u0026thinsp;7.14 \u0026micro;s for ZC. The values of parameter α indicate broader relaxation time distribution for C and ZC samples, correlating with higher dielectric values. Impedance analysis demonstrates that all samples exhibit decreasing impedance with increasing frequency, attributed to the activation of free charge carriers. The C sample exhibits the highest impedance across the frequency range, likely due to lattice disorder caused by cation size mismatches, which created barriers for charge carrier movements. In contrast, the ZC composite exhibits lower impedance than pure Z and C samples. This reduction arises from the formation of additional defects and grain boundaries at the interfaces between Z and C crystallites in ZC sample, which facilitates the charge carrier transport. AC conductivity measurements confirm the CBH mechanism as the dominant conduction process, with the ZC composite showing the highest conductivity across the studied frequency range.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eDeclaration of interest statement\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article.\u003c/p\u003e\n\u003ch2\u003eData availability\u003c/h2\u003e\n\u003cp\u003eAll the data recorded and analyzed during the present investigations are included in this published article.\u003c/p\u003e\n\u003ch2\u003eCompeting Interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eI testify on behalf of all co-authors that our article submitted to Journal of Sol Gel Science and Technology:Title: Investigations on structural and electrical properties of ZnO based nanoparticles and compositeAll authors: V.R. Rathod, Mehul Parmar, Himanshu Dadhich, N.A. Chondagar, Khushal Sagapariya, Uday Kareleeya, R.K. Trivedi, P.P. Bardapurkar, Karan Rathod, S.B. Kansara, N.A. Shah, P.S. Solanki..(1) This material has not been published in whole or in part elsewhere.(2) The manuscript is not currently being considered for publication in another journal.(3) All authors have been personally and actively involved in substantive work leading to the manuscript, and will hold themselves jointly and individually responsible for its content.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eCorresponding author Himanshu Dadhich is thankful to all coauthors for supporting this article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eS.A. Wolf, D.D. Awschalom, R.A. Buhrman, J.M. Daughton, S. Von Molnar, M.L. Roukes, A.Y. Chtchelkanova, D.M. 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Technol.93 (2020) 666\u0026ndash;677.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cdiv class=\"gridtable\"\u003e\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eRietveld refined parameters for Z, C and ZC composite samples.\u003c/div\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eParameters\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZnO (Z)\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C)\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZC Composite\u003c/div\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZnO (Z)\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C)\u003c/div\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003ea(\u0026Aring;)\u003c/span\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.2491\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e4.6793\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.2490\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e4.6916\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eb(\u0026Aring;)\u003c/span\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.2491\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.4239\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.2490\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.4304\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003ec(\u0026Aring;)\u003c/span\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e5.2051\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e5.1294\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e5.2048\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e5.1204\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eR\u003c/span\u003e\u003csub\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eF\u003c/span\u003e\u003c/sub\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.517\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e9.762\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e4.2561\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e8.1822\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eR\u003c/span\u003e\u003csub\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eBragg\u003c/span\u003e\u003c/sub\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e3.771\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e10.68\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e2.8590\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e5.2406\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eR\u003c/span\u003e\u003csub\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eWP\u003c/span\u003e\u003c/sub\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e19.10\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e24.50\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e20.00\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eR\u003c/span\u003e\u003csub\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eexp\u003c/span\u003e\u003c/sub\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e12.96\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e16.71\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e15.25\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eR\u003c/span\u003e\u003csub\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003eP\u003c/span\u003e\u003c/sub\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e15.30\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e30.90\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e21.80\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e\u0026chi;\u003c/span\u003e\u003csup\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e2\u003c/span\u003e\u003c/sup\u003e\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e2.18\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e2.15\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e1.72\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eMaximum barrier height (W\u003csub\u003em\u003c/sub\u003e) and Power exponent (\u0026eta;) calculated Jonscher\u0026rsquo;s power law formula for all three samples.\u003c/div\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"3\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eSample code\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003ePower Exponent (\u0026eta;)\u003c/div\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eMaximum Barrier Height\u003c/div\u003e\n \u003cdiv class=\"SimplePara\"\u003e(W\u003csub\u003em\u003c/sub\u003e in MeV)\u003c/div\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZ (ZnO)\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e0.17\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e189.87\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eC (Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO)\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e0.53\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e330.01\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003eZC\u003c/div\u003e\n \u003cdiv class=\"SimplePara\"\u003e(ZnO: Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO)\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e0.76\u003c/div\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cdiv class=\"SimplePara\"\u003e646.28\u003c/div\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Structural properties, Electrical properties, Sol–Gel, Co–precipitation, ZnO, Nanoparticles","lastPublishedDoi":"10.21203/rs.3.rs-5797355/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5797355/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDiluted magnetic semiconductors (DMS) have emerged as promising candidates for spintronic devices, offering a unique combination of semiconducting and magnetic properties. In the present study, ZnO (Z) and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (C) nanostructured materials were synthesized using sol\u0026ndash;gel and co\u0026ndash;precipitation methods, respectively. Their composite, ZnO: Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO (ZC), was fabricated to investigate the structural and electrical properties. X\u0026ndash;ray diffraction (XRD) analysis confirms the hexagonal wurtzite phase and reveals a reduced crystallite size and suppressed lattice strain across the lattice of ZC composite, as compared to the pure phases (i.e. Z \u0026amp; C). Rietveld refinements and Williamson\u0026ndash;Hall (W\u0026ndash;H) analysis further established changes in lattice parameters and strain effect. The dielectric constant, measured for a frequency range between 20 Hz and 2 MHz, shows a significant enhancement in its values for composite material which can be attributed to the interfacial polarization and oxygen vacancies. Impedance spectroscopy reveals lower impedance in the ZC composite indicating better conduction pathways due to enhanced defect density and grain boundary interactions. AC conductivity, analyzed using Jonscher's power law, demonstrates that the correlated barrier hopping (CBH) mechanism governs the conduction, with ZC composite sample exhibiting the highest conductivity among all the three samples. These findings suggest that the composite exhibits improved dielectric and electrical performance due to synergistic effects between ZnO and Zn\u003csub\u003e0.2\u003c/sub\u003eCu\u003csub\u003e0.8\u003c/sub\u003eO phases, making it a promising material for electronic and optoelectronic applications.\u003c/p\u003e","manuscriptTitle":"Investigations on structural and electrical properties of ZnO based nanoparticles and composite","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-13 08:51:11","doi":"10.21203/rs.3.rs-5797355/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b55ebfb2-7b3f-4869-bef1-efddc829a529","owner":[],"postedDate":"January 13th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-01-20T06:09:06+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-13 08:51:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5797355","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5797355","identity":"rs-5797355","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}