Stable Lateral Heterostructure in All-inorganic Perovskites with Suppressed Halide Ions Migration

Stable Lateral Heterostructure in All-inorganic Perovskites with Suppressed Halide Ions Migration | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Stable Lateral Heterostructure in All-inorganic Perovskites with Suppressed Halide Ions Migration Xiujuan Zhuang, Junyu He, Yang Li, Tongqing Sun, Anshi Chu, Min Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4634105/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 The dangling bonds and surface defects at the grain boundaries of three-dimensional (3D) perovskite provide convenient conditions for non-radiative recombination and ion migration, which degrades the stability of perovskite materials. Herein, we prepared single-component lateral epitaxial heterostructure perovskites using a one-step solution method by rare earth Er 3+ doping. Through photoluminescence (PL) and time-resolved PL spectroscopy, the erbium-doped CsPb(Br x I 1−x ) 3 heterostructure microplate forms a stable dual-wavelength emission with enhanced PL intensity and lifetime. We find that rare earth doping can effectively suppress ion migration by improving the ion migration barrier and facilitating the intrinsic stable heterostructure formation with desired dual-wavelength emission and improved radiation recombination rate. The discovery sheds a new perspective on inhibiting ion migration by trivalent B-site doping of rare earth ions and provides a basis for the preparation of single-component heterostructure perovskite. Physical sciences/Materials science/Materials for optics Physical sciences/Optics and photonics/Optical materials and structures Physical sciences/Optics and photonics/Optical physics Physical sciences/Optics and photonics/Optical techniques dual-wavelength emission lateral epitaxial heterostructure all-inorganics perovskite rare earth doping ion migration energy funnel Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Three-dimensional (3D) metal halide perovskites (MHPs) composed of ABX 3 (A stands for monovalent metal cation such as Cs + , B is a divalent metal cation, X refers to halide anions) 1,2 crystallographic structure present a uniquely promising material for next-generation optoelectronic applications, such as solution-processed solar cells 3,4 , light-emitting diodes 5,6 , detectors and lasers 7–9 . Although their inherently soft crystal lattice allows large tolerance to lattice mismatch 10–13 , they also enable high intrinsic ion mobility due to the dangling bonds at the grain boundaries and surface defects. For this reason, mixed MHPs have been demonstrated to undergo a high ion migration velocity and a hysteresis effect under light illumination or an electric field, which degrade the performance of materials and signifies a challenge for commercialized optoelectronic devices 14 . Their high intrinsic ion mobility makes the epitaxial growth of atomically sharp heterostructures challenging because the ion diffusion usually leads to a large junction width 15,16,17 . More generally, it is challenging to prepare single-component halide heterostructures by one-step method due to the close preparation temperature between the different components. Due to this, the complicated two-step solution-based or chemical vapor deposition (CVD) method is usually used to prepare heterostructure MHPs, but some experimental studies have shown that these methods are more likely to form alloying phase perovskites rather than heterostructures perovskites 18–20 . Therefore, the effective inhibition of ion migration in MHPs is necessary for the further preparation of single-component heterostructure perovskites. Various attempts to suppress this light-induced ion migration in mixed MHPs have been adopted, such as increasing the concentration of larger halogen ions or substituting A-site ions with small alkali metal cations 21–24 . Besides, the B-site replacement, such as the incorporation of bivalent metal ions (Mn 2+ , Cu 2+ , Sn 2+ , Zn 2+ ) and tervalent ions (Bi 3+ , Ce 3+ , Yb 3+ ), has also been considered as another promising avenue which could significantly improve the stability of MHPs and optimize the photophysical properties 25,26 . Among a variety of B-site dopants, the rare earth ion Er 3+ has been proven to promote the lattice distortion of perovskites octahedral frame due to heterovalent doping, and the shallow defect level between the valence band and conduction band could significantly improve the luminous intensity and color purity of MHPs 27,28 . More importantly, since the electrons in the 4f orbital are effectively shielded by the electrons in the outer 5s and 5p layers, Er 3+ doping can protect perovskites from the disturbance of the ambient temperature, which is an ideal dopant. In this work, Er-doped all-inorganic perovskite lateral heterostructure microplates, CsPb(Br x I 1−x ) 3 , were prepared by a simple one-step solution method. Both the ions migration inhabitation and the heterostructure formation mechanism were explored through photoluminescence (PL) spectroscopy and time-resolved PL (TRPL) spectroscopy. We proposed that Er 3+ is more inclined to combine with the larger size I − to form the ErI 5 polyhedron, while the Pb 2+ is preferred to combine with the smaller size Br − to form the PbBr 6 octahedra, thus promoting the formation of stable intrinsic heterostructure. Besides, Er doping relieved the lattice stress between the different halides and eliminated the dangling bonds at the grain boundaries, effectively increasing the ion migration barrier and radiation recombination efficiency. Therefore, the rapid movement of halogen ions was inhibited. The discoveries provide a basis for studying ion migration inhabitation mechanisms for MHP systems and a platform for optoelectronic devices with multiple emission channels, including multi-channel photodetectors, solar cells, and lasers 29 . Results and Discussion The one-step solution spin-coating method was used to prepare Er-doped CsPb(Br x I 1−x ) 3 microplates (Er: CsPb(Br x I 1−x ) 3 ) by adding an Er(NO 3 ) 3 powder into the CsPb(Br x I 1−x ) 3 reaction system (see Methods and Fig. S1 in Supporting Information). The Er concentrations in host perovskite were controlled by tuning the mole ratio of source materials. As schematically shown in Fig. 1 a, the Er 3+ dopants tend to occupy the B-site and replace the host Pb 2+ in the perovskites lattice 28 . The heterovalent doping of Er 3+ could distort the adjacent octahedrons and induce lattice distortion. The lattice structure of prepared Er: CsPb(Br x I 1−x ) 3 microplates with different Er concentrations (0–5% in precursor solutions) was characterized by X-ray diffraction (XRD) tests, as shown in Fig. 1 b. As indicated from the diffraction peaks, all perovskites have cubic phase lattice structures (PDF#75–0412) with prominent Bragg diffraction peaks corresponding to (100), (110), and (200) planes 29 . With increasing the Er concentration, the (200) diffraction peak constantly exhibits a slight shift toward the larger angle (Fig. 1 c), suggesting a certain extent of lattice shrinkage. In our case, the observed lattice shrinkage is due to the Er 3+ with a small ionic radius (89 pm) replacing the larger host Pb 2+ (119 pm). Simultaneously, the Er doping could also induce the band gap expansion of MHPs perovskites, as manifested in the blue-shift of absorption spectra (Fig. 1 d) caused by shrink lattice. To study the influence of the Er doping on the micromorphology and element distribution, scanning electron microscope (SEM) images and elemental mappings of typical Er:2%-CsPb(Br x I 1−x ) 3 microplate were conducted (Fig. e-j and Fig. S2). The SEM images indicate that both undoped and doped samples exhibit a square shape with a side length of ~ 3 µm (Fig. 1 e and h). It is worth noting that the distribution of I − is different in the host and doped samples (Fig. 1 g and j). According to the Energy Dispersive X-ray (EDX) results, the Cs, Pb, Br, and I elements are uniformly distributed in the host microplate, and the estimated chemical formula for this sample is CsPb(Br 0.77 I 0.23 ) 3 (Table S1 ). According to EDX dot scan analysis, the Br/I ratio in the central (Fig. 1 e position 1) and the edge region (Fig. 1 e position 2) are closed, demonstrating the uniformity of the host sample. In the Er-doped sample, the Br/I ratio in the central region (Fig. 1 h position 1) is 4.7:1, higher than the 3:1 of the outer region (Fig. 1 h position 2) (Table S1 ). These results imply that the Er-doped microplate tends to form a halogen heterogeneous structure, where more I – inclines to distribute at the edge region of the microplate than the central region, as schematically illustrated in Fig. 1 k. It resembles a planar heterostructure with the narrow bandgap perovskites in the edge region and wide bandgap perovskites in the central region. To further explore the influence of Er-doping on the dealloying and ion migration characteristics, we carried out the PL spectral experiment under continuous light-soaking. A continuous wave laser with a wavelength of 405 nm was used as the soaking light source. Figure 2 a and e show the pseudo-color images of PL spectra variation as a function of light-soaking time for the CsPb(Br 0.77 I 0.23 ) 3 and Er:2%-CsPb(Br 0.77 I 0.23 ) 3 , respectively. A significant photoinduced phase separation is generated in the host perovskite. As shown in Fig. 2 a, the PL spectra exhibit a single alloying peak at ~ 590 nm at the initial soaking time (t = 0 s). Then, the peak intensity decreases quickly within 5 seconds of light-soaking time, and a new PL peak near 700 nm appears simultaneously. After 5 seconds of light-soaking, the PL intensity at 590 and 700 nm still maintains an opposite variation tendency with extending the light-soaking time but with a much slower intensity variation rate (Fig. 2 b and Fig.S3). During the photoexcitation, the more easily mobile I − migrates to the edge region of the microplate, resulting in a light-induced dealloying process. The structural formula of two segregated perovskites with different halide composition ratios was approximately CsPb(Br 0.75 I 0.25 ) 3 and CsPb(Br 0.3 I 0.7 ) 3 as determined from their PL peak (The calculation procedure is shown in SI), which correspond to a wide bandgap phase (WBP) and a narrow bandgap phase (NBP), respectively. The ion migration rate of the NBP can be obtained by fitting the first-order rate constant K forward according to the following formula 30 : $$\frac{{I}_{NBP}}{{I}_{sat}}=1-{e}^{-{K}_{forward}t}$$ 1 where I NBP is the PL intensity of NBP, and I sat is the saturation emission intensity. According to the fitting results, the NBP has a fast ion migration rate with the K forward of 0.42 S − 1 in the first 5 seconds of light-soaking and then decreases to 0.09 S − 1 after 5 seconds. This rapid ion migration rate may come from the unbonded dangling bond on the surface of the single crystal microplate, which provides a path for the migration of I − , and the long carrier diffusion length of MHPs also provides a convenient condition for I − to move to the edge of the microplate (Fig. 2 d). Unlike the host sample, the Er-doped microplate exhibits distinct dual-peak PL emission at 580 and 690 nm at the 0-second light-soaking time and maintains this dual PL peak during the recorded entire light-soaking (Fig. 2 e). The results imply that the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate exhibits intrinsic phase segregation even before the light-soaking. Unusually, the PL intensity of both NBP and WBP increases linearly with the extension of light-soaking time, but the PL rise rate of 690 nm is significantly higher than that of 580 nm (Fig. 2 f). The light-soaking here plays an essential role in suppressing the non-radiative recombination, which was also reported by "photo-passivation." It can be speculated that the suppression of non-radiative recombination originates from the photoinduced defects repairing process 28 . Besides, with the incorporation of Er 3+ , shallow level defects, including Er 4f energy level, are introduced between the valence band and conduction band, thus reducing the difficulty of carrier transition and increasing the PL intensity 27 . The WBP and NBP were approximately determined as CsPb(Br 0.78 I 0.22 ) 3 and CsPb(Br 0.56 I 0.44 ) 3 , respectively (see Fig. 2 g and SI). According to the spectral characterization, the host perovskite undergoes an obvious ion migration process under light-soaking and realizes the evolution from a single alloy phase to two phases with different Br/I ratios (bandgap). After doping, Er 3+ in the host perovskite eliminates the dangling bond at grain boundry, reducing the ion migration channel. At the same time, lattice shrinkage and heterovalent doping caused by small size further promote the lattice distortion of the octahedron, increase the ion migration barrier, thus the ion migration is inhibited effectively (Fig. 2 h). Figure 3 a and c show the PL mappings of CsPb(Br 0.77 I 0.23 ) 3 and Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplates collected at WBP and NBP region, respectively. The PL mappings indicate that both the host and doped perovskite form the heterostructure, with WBP mainly distributed in the center and NBP distributed on the margin of the microplate. Although both PL mappings indicate similar mapping results, the heterostructure formation mechanism is significantly different. For the host MHPs, this heterostructure is a dynamic process induced by ion migration, producing a light-induced heterostructure (Fig. 3 b). The metastable uniform single alloy-phase perovskite is distributed on the surface of the microplate in dark conditions. Under light excitation, the I − continuously moved away from the alloy-phase perovskite which is located at the central area of the light excitation, and this process is a dynamic component separation process. The long carrier diffusion characteristics of MHPs enable I − to migrate to the edge of the microplate. As a result, a light-induced planer heterostructure in the host microplate is formed. For the Er-doped microplate, both elements mapping and PL results indicate the heterostructure is intrinsic before the photoexcitation. During the preparation process, a part of Er 3+ replaced Pb 2+ , resulting in lattice shrinkage and thus generating lattice stress in the MHP lattice. To eliminate this non-uniformity stress, during the annealing process, the Er 3+ preferentially coordinates with the large-sized I − to form a polyhedron with the longer Er-I bond, which could offset the lattice shrinkage caused by the small-sized B-site ions to a certain extent. As a result, more Br − are in the PbX 6 octahedron distributed at the center of the microplate, and more I − are in the ErX 5 polyhedron distributed on the edge, maintaining a stable state. Synthetically, the intrinsic heterostructure is formed (Fig. 3 d). Due to the bandgap difference between the segregated MHP phase, the carriers at the heterointerface will migrate from the WBP to the NBP through a carrier funnel process 31 . A time-resolved photoluminescence (TRPL) experiment was employed to systematically investigate the heterostructure carrier dynamics and the effect of light-induced ion migration on the heterointerface during light-soaking. Using a femtosecond pulse laser with a wavelength of 400 nm to excite the entire sample, the streak camera images at the different light-soaking times were taken respectively, and the signal collection time was maintained 1 minute for each acquisition. As shown in Fig. S4, in the host CsPb(Br 0.77 I 0.23 ) 3 microplate, the WBP exhibits a lifetime of 227 ps, while the NBP exhibits a longer PL lifetime of 547 ps. This result is consistent with the literature report, where I-rich perovskite has a greater dielectric constant compared with Br-rich perovskite, so the carriers have a strong shielding effect on defect impurities and reducing the radiation decay rate, resulting in a longer lifetime 32 . Figure 4a 1 and a 2 demonstrate the streak camera images from the WBP and NBP of the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate. The PL dynamic curves were extracted from these images and shown in Fig. 4 b, where the WBP (580 nm) exhibits a PL rise time with a time constant of 10 ps and a single exponential PL decay with a lifetime of 538 ps, while NBP exhibits a prolonged PL rise time fitted by a single exponential decay with a lifetime of 649 ps. The rise time of the dynamic curve from the WBP can be found close to the instrument response function (IRF, ~ 10 ps). Differently, the rise time of the NBP is about 33 ps, which is much longer compared to the IRF. The prolonged rise time in the NBP section implies an extra energy inflow, which comes from the carriers' migration from the WBP to the NBP through a carrier funnel process 33 . The inset in Fig. 4 c designates the type-I band alignment diagram of the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate to elaborate the carriers' funnel process. The valence band (conduction band) of the WBP is lower (higher) than that of the NBP perovskite. The band offsets between the two different components could be regarded as an energy barrier to operate the NBP component, acts as an energy sink to capture the carriers from the high-energy WBP aided by large mixed perovskite diffusion lengths, thus converging the carriers at the low-energy region, then the PL intensity of the NBP continuously enhanced through radiation recombination. As shown in Fig. 4 c, the lifetimes of both WBP and NBP constantly increased with the increase of light-soaking time. This is significantly different from the undoped system, where the lifetimes of the WBP (NBP) demonstrate a continuous decrease (enhancement) due to the carrier funnel effect and ion migration (Fig. S4a and b). The lifetimes increasing can be expected in the Er-doping MHPs because when Er 3+ replaces Pb 2+ , the ionic bond in the MHPs crystal lattice will be strengthened, and the density of states in the conduction band increases, thus improving the static dielectric constant and reducing the surface defect. Additionally, the internal lattice defects will participate in the carrier recombination process due to the heterovalent doping of Er in the host perovskite, increasing the radiation recombination site and improving the lifetimes. To verify the intrinsic planar heterostructure in the Er-doped perovskite microplate, the diffusion behavior of carriers in the NBP region was studied using a spatial-resolved PL image, which was obtained by the streak camera (see experimental section). Figure 4 d indicates the carriers diffusion image from the NBP of the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate in the time scale of 0-500 ps. The PL intensity I PL (x,t) of the diffusion time-dependent spatial-resolved PL image could be well fitted by a Voigt function 34,35 : I PL ( x, t )∝exp[− x 2 /2σ( t ) 2 ] ( 2 ) Δσ 2 = σ 2 (t) − σ 2 (0) = 2Dt ( 3 ) 36 where x is the one-dimensional spatial coordinate, σ 2 (t) and Δσ 2 represent the variance of the carrier distribution as a function of time (t), and the mean-squared displacement describes the time evolution of space broadening, respectively. D is the carrier diffusion coefficient, which can be obtained by Eq. (3). As illustrated in the carriers diffusion profiles for the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate after the light excitation of 0 and 500 ps (Fig. 4 e), the half-peak width of PL spectra at 500 ps shows a slight broadening compared to that at 0 ps, which confirms the carrier diffusion at the heterostructure interface. The D value for the Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate is about 0.035 cm 2 /s, which is significantly reduced compared to that of the undoped sample, 0.07 cm 2 /s. According to Einstein's relation, the diffusion coefficient is proportional to mobility. It can be considered that Er doping inhibits the migration of carriers in NBP due to the lattice distortion caused by the substitution of trivalent ions for divalent. The reduced D value also implies the prolonged radiative recombination lifetime and increased PL intensity, which is favorable for applying light-emitting devices. According to the PL and TRPL spectral analysis above, there are two mechanisms of coexistence and competition in the Er-doped MHPs: ( 1 ) the decrease of PL and lifetime of WBP caused by ion migration and ( 2 ) the increase of PL and lifetime caused by Er doping. To verify the assumption, we synthesized a series of MHP microplates with different Er concentrations to study the effects of varying dopant concentrations on lifetimes and ion migration rates. Figure 5 a displays the light-soaking time-dependent lifetimes for WBP with five different Er concentrations (1%-5%). For each Er concentration, the average lifetime values were statistics analyzed from eight MHP samples (Table S3 to S7) and the lifetime value at each light-soaking time (1 to 8 min) are exhibited in Fig. 5 a. For Er concentrations of 1%, the average lifetime of WBP still declines with the extension of light-soaking time, which proves that ion migration is dominant in MHPs with low Er concentration (black curve in Fig. 5 a). When Er concentration exceeds 1%, the average lifetime of WBP perovskite increases gradually and reach a peak with the doping concentration is 3%, confirming the promotion of radiation recombination enabled by the addition of Er 3+ , and at this time the ion migration is at a disadvantage. When Er concentration continuously increases to 4% or 5%, the lifetime of WBP perovskite still exhibits an upward trend but with a slower speed because the excessive doping concentration will introduce more deep-level defects, resulting in the deterioration of perovskite performance. Figure 5 b exhibits a qualitative depiction of the relationship between PL intensity rise rate and Er concentration of NBP perovskite by plotting I NBP /I sat as a function of light-soaking time (extracted from Fig. S5), where K is a valuable indicator to regulate the time evolution of PL intensity. Similar to the regularity of lifetime change, the K rises first with the increased Er concentration, from 0.0134 s − 1 of Er:0% to 0.0372 s − 1 of Er:3%. Then, the K value would reduced when the Er concentration is further increased due to excessive defects. Here, the PL intensity of the NBP is used for comparison to circumvent potential ambiguity and difficulty because when Er concentration is low (0%), the ion migration process dominates, and the PL intensity of WBP is gradually reduced, which is inconvenient for comparison. This process can also be explained by Fig. 5 c, that the ion migration plays a significant role when the Er doping concentration is low; in this situation, the carriers migrated from the WBP to the NBP by the carrier funnel effect, shortening the PL intensity and lifetime of WBP. With the increase of Er concentration, Er inhibits ion migration and promotes radiation recombination, contributing to the rise of PL and lifetime. We have confirmed that the lifetime of the WBP perovskite shows a time-dependent decay due to the dominant ion migration in the Er:1%-CsPb(Br 0.77 I 0.23 ) 3 sample (Fig. 5 a black curve). Some studies have reported that a small Br/I ratio could effectively inhibit ion migration. Therefore, we select perovskites with a smaller Br/I ratio of 3:2 and 2:3 (Er:1%-CsPb(Br 0.6 I 0.4 ) 3 and Er:1%-CsPb(Br 0.4 I 0.6 ) 3 ), which possesses inhibited ion migration rate than Er:1%-CsPb(Br 0.77 I 0.23 ) 3 for the comparative experiment. For both samples, the lifetime of WBP perovskite presents a time-dependent rise (Fig S6), which is undoubtedly different from Er:1%-CsPb(Br 0.77 I 0.23 ) 3 , proving that the radiation recombination induced by Er doping is dominant after the inhibition of ion migration, it is further confirmed that these two mechanisms can be regulated. Both host and Er-doped perovskite thin films were prepared to verify the improved optical stability of Er-doped MHPs, and light-soaking time-dependent PL experiments were carried out (Fig. S7). The host perovskite film exhibits a rapid ion migration phenomenon, and the PL peak is continuously blue-shifted with the extension of the light-soaking time (Fig. S7a). Meanwhile, the PL peak shifted slightly for the Er-doped perovskite film, demonstrating the improved optical stability by Er doping (Fig. S7b). Additionally, the initial PL intensity of the Er-doped perovskite is much higher than that of the host perovskite (Fig. S7c), which further suggests that Er doping can not only improve the stability of the system by inhibiting ion migration but also increase the luminescence performance. The formation of heterostructure and PL mechanism of Er: CsPb(Br x I 1−x ) 3 is proposed in Fig. 6 . The homogeneous alloy phase in the host CsPb(Br x I 1−x ) 3 microplate exhibits a light-induced spatially dealloying process, which is caused by migration and forms light-induced transient heterostructures. The light-soaking here activates the I − migration. Differently and interestingly, the Er: CsPb(Br x I 1−x ) 3 microplate tends to form an intrinsic heterostructure that is not dependent on photoexcitation. It shows stable dual-wavelength emission in the spectra. The rule of the light-soaking in the Er: CsPb(Br x I 1−x ) 3 sample is light-induced shallow defect passivation and increased PL intensity. ASSOCIATED CONTENT Conclusion In summary, Er-doped all-inorganic perovskite lateral heterostructure microplates, CsPb(Br x I 1−x ) 3 , were prepared by a simple one-step solution method. The Er: CsPb(Br x I 1−x ) 3 heterostructure microplate forms a stable dual-wavelength emission with enhanced PL intensity and lifetime. Compared to the undoped CsPb(Br x I 1−x ) 3 , the introduction of Er dopant into the perovskite effectively inhibits the ion migration and prompts the formation of the intrinsic heterostructure. Light-induced halide ions migration and luminescence enhancement caused by Er-deposited radiation recombination sites are exhibited simultaneously in the system. By optimizing the Er concentration and halogen ratio, ions migration and radiation recombination rate can be controlled to achieve an equilibrium. These results underline the basis for light-induced ion migration and pave the path for pursuing all inorganic perovskites with rare earth ion doping applied in multi-wavelength optoelectronic devices and commercially viable integrated circuits. Methods Preparation of microplates. Both CsPb(Br 0.77 I 0.23 ) 3 and Er-CsPb(Br 0.77 I 0.23 ) 3 were prepared using a one-step solution coating method. For the synthesis of CsPb(Br 0.77 I 0.23 ) 3 , lead bromide (0.183 g, PbBr 2 , 99.99%, Aladdin), Cesium bromide (0.106 g, CsBr, 99.99%, Aladdin) were dissolved into 5 mL dimethyl sulfoxide (DMSO, AR, Macklin), then adding 1 mL deionized water and stirred for six hours at 323 K. Then, the moderate precursor solution was dripped onto the cleaned ITO substrate and spin-coated at 500 rpm for 30 s. Finally, put the substrate on the hot flake, annealing for 10 minutes at 393 K-473 K. For synthesizing Er-CsPb(Br 0.77 I 0.23 ) 3 , erbium nitrate (0.1 g, Er(NO 3 ) 3 , 99.99%, Mreda) was dissolved into 20 mL deionized water solution and stirred for six hours at 323 K. Then 0.5 g, 1 g, 1.5 g, 2 g, and 2.5 g of erbium nitrate precursor solution were dropped into CsPb(Br 0.77 I 0.23 ) 3 precursor, respectively, and continued stir for 6 hours to form solutions with different Er doping concentrations. The stirred precursor solution was repeated and annealed in the spin coating process. PL Spectra and Mapping Measurements. Steady-state PL spectra were detected by a confocal microscope system (WITec, alpha-300). The continuous laser at 405 nm was introduced to the confocal system and focused on the samples through the space light module through the charge-coupled device camera (DFK 23GV024) and an objective lens (50 ×, Zeiss, 0.75 numerical aperture). The in-situ PL signals were detected by a spectrometer (150 g/mm grating). PL mapping measurements were conducted by a 50-fold lens to focus on the center of the microplate, and a ~ 20×20 µm square frame was used to select the tested area to test the PL spectra of each point in the area and image. The integration time of the scan was 0.1s. TRPL and Carrier Diffusion Experiments. TRPL experiments of WBP and NBP were measured by using a confocal microscope (WITec, alpha-300) as the collection device; the PL signal was reflected into the streak camera (C10910, Hamamatsu) by Ag mirrors with 400 nm laser pulses (Ti: sapphire laser with a repetition rate of 80 MHz and a pulse width of 80 fs) as the exciting light. The 400 nm wavelength output light was produced by an 800 nm laser from a mode-locked oscillator (Tsunami 3941-X1BB, Spectra-Physics) positioned after a BBO crystal. The excitation light was focused onto the sample by an objective lens (50 ×, Zeiss, 0.75 numerical aperture) with a spot diameter of ∼3 µm from the top. The carrier diffusion experiment was also measured by introducing the PL signal into the streak camera (C10910, Hamamatsu) to measure the spatial resolution spectra. The NBG PL signal is collected by placing a 600 nm long wave pass filter in front of the streak camera light module, then setting the collection center wavelength in the test system at 0 µm to avoid splitting the light, then the spatial diffusion behavior of NBP's carriers were recorded by spatial-resolved mapping image. Declarations AUTHOR INFORMATION Corresponding Author Xiujuan Zhuang, College of Semiconductors (College of Integrated Circuits), Hunan University, China Email: [email protected] Author Contributions Junyu He carried out the conception of experimental ideas, the analysis of data, and the writing of the manuscript; Xiujuan Zhuang completed the verification of experimental data, the provision of ideas, and the revision of the manuscript; Yang Li and Tongqing Sun performed the optical characterizations; Anshi Chu and Min Li completed the preparation of experimental reagents; All authors discussed the results and commented on the manuscript. Notes The authors declare no competing financial interest. Acknowledgments All authors are grateful to the National Natural Science Foundation of China (Nos. 61635001). Supporting Information . The contents of the supporting information are listed as follows: Flow chart of perovskite preparation by solution spin coating; SEM image EDS mapping of typical CsPb(Br 0.77 I 0.23 ) 3 and Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate; EDX spectra of both microplate of position 1 and position 2 in figure 1e and h; I NBP /I sat curve of Er:2%-CsPb(Br 0.77 I 0.23 ) 3 microplate with different light soaking time; Time-resolved PL curves of the CsPb(Br 0.77 I 0.23 ) 3 microplate; Fitting results of the parameters of the dynamic curves in Figure 4b; Lifetime table of CsPb(Br 0.77 I 0.23 ) 3 with different Er concentration; Time-dependent PL spectra of CsPb(Br 0.77 I 0.23 ) 3 microplates with different Er concentrations; Time-dependent PL spectra and TRPL results of 1%-Er: CsPb(Br x I 1-x ) 3 with varies Br/I ratio; Time-dependent and steady-state PL spectrum of CsPb(Br 0.77 I 0.23 ) 3 and Er:2%-CsPb(Br 0.77 I 0.23 ) 3 perovskite films. 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Adv Funct Mater 32:2107086 Cai T et al (2020) Mn2+/Yb3 + Codoped CsPbCl3 Perovskite Nanocrystals with Triple-Wavelength Emission for Luminescent Solar Concentrators. Adv Sci 7:2001317 Draguta S et al (2017) Rationalizing the light-induced phase separation of mixed halide organic-inorganic perovskites. Nat Commun 8 Oddo AM et al (2023) Energy Funneling in a Noninteger Two-Dimensional Perovskite. Nano Lett 23:11469–11476 Huang L et al (2018) Composition-Graded Cesium Lead Halide Perovskite Nanowires with Tunable Dual-Color Lasing Performance. Adv Mater 30:1800596 Zheng WH et al (2019) Carrier-Funneling-Induced Efficient Energy Transfer in CdSxSe1-x Heterostructure Microplates. Acs Energy Lett 4:2796–2804 Akselrod GM et al (2014) Subdiffusive Exciton Transport in Quantum Dot Solids. Nano Lett 14:3556–3562 Ziegler JD et al (2020) Fast and Anomalous Exciton Diffusion in Two-Dimensional Hybrid Perovskites. Nano Lett 20:6674–6681 Sun R et al (2022) Efficient single-component white light emitting diodes enabled by lanthanide ions doped lead halide perovskites via controlling Forster energy transfer and specific defect clearance. Light-Sci Appl 11:340 Additional Declarations There is NO Competing Interest. Supplementary Files SI.docx 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-4634105","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":319567921,"identity":"17347973-2c3a-4125-8254-c7e83a55591b","order_by":0,"name":"Xiujuan Zhuang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA20lEQVRIiWNgGAWjYDACCQjFzA9hMJOgRXIGqVoYDG4Qq0V+do/h54Jfh9mNb/cek2CosE5sYD97AK8WxjlnjKVn9qUxm905lybBcCY9sYEnLwGvFmaJHANp3h4bZrMbOWYSjG2HExskeAzwamGTyDH+zdsjwWw8A6TlHxFaeCRyzKR5ftgwG0iAtDQQoUVCIq3MmrchjVniRo6xRcKxdOM2nhz8WuRnJG++zfPncDL/jBzDGx9qrGX72c/g1wIGjG0MyWBGAsh3hNWDwB8GO+IUjoJRMApGwYgEALvTO0avyrJiAAAAAElFTkSuQmCC","orcid":"","institution":"Hunan University","correspondingAuthor":true,"prefix":"","firstName":"Xiujuan","middleName":"","lastName":"Zhuang","suffix":""},{"id":319567922,"identity":"315e6ea4-c72f-4127-ac53-27f8444fae34","order_by":1,"name":"Junyu He","email":"","orcid":"","institution":"Hunan University","correspondingAuthor":false,"prefix":"","firstName":"Junyu","middleName":"","lastName":"He","suffix":""},{"id":319567923,"identity":"01899829-0886-44fc-865d-878172f70274","order_by":2,"name":"Yang Li","email":"","orcid":"","institution":"Hunan University","correspondingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Li","suffix":""},{"id":319567924,"identity":"1e7cc246-5bf7-4e77-8431-65986ab85b5e","order_by":3,"name":"Tongqing Sun","email":"","orcid":"","institution":"Hunan University","correspondingAuthor":false,"prefix":"","firstName":"Tongqing","middleName":"","lastName":"Sun","suffix":""},{"id":319567925,"identity":"5a9d5a32-6362-4e5a-9a4b-cc707b94bc3e","order_by":4,"name":"Anshi Chu","email":"","orcid":"","institution":"Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University Changsha 410082, P. R.China","correspondingAuthor":false,"prefix":"","firstName":"Anshi","middleName":"","lastName":"Chu","suffix":""},{"id":319567926,"identity":"a3974ecb-c433-4780-b50f-f03fcb6e76fb","order_by":5,"name":"Min Li","email":"","orcid":"","institution":"Hunan University","correspondingAuthor":false,"prefix":"","firstName":"Min","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2024-06-25 06:50:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4634105/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4634105/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":59274347,"identity":"0408b251-c5ad-4dd2-8262-daf9625e2642","added_by":"auto","created_at":"2024-06-28 13:39:51","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":636048,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges of morphology, lattice structure, and bandgap by Er incorporation.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e Diagram of Er doping induced Lattice structure contraction in CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1-x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e. \u003cstrong\u003eb\u003c/strong\u003e XRD patterns of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates with different Er\u003csup\u003e3+\u003c/sup\u003e doping concentrations. \u003cstrong\u003ec \u003c/strong\u003eZoomed-in XRD patterns of the (200) diffraction peak. \u003cstrong\u003ed\u003c/strong\u003e Absorption spectrum of CsPbBr\u003csub\u003e2.32\u003c/sub\u003eI\u003csub\u003e0.68\u003c/sub\u003e and Er:5%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e. \u003cstrong\u003ee \u003c/strong\u003eSEM image of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e. \u003cstrong\u003e(f-g) \u003c/strong\u003eEDS mapping of typical CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e.\u003cstrong\u003e h\u003c/strong\u003e SEM image of Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates.\u003cstrong\u003e (i-j) \u003c/strong\u003eEDS mapping of typical Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate. \u003cstrong\u003ek \u003c/strong\u003eSchematic diagram of the atomic structure of heterostructure formed by Er doping.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/fe1ac1773c9961985c29fd4c.png"},{"id":59274348,"identity":"70cbd83e-d0da-4856-acb4-f872d57ba4bb","added_by":"auto","created_at":"2024-06-28 13:39:51","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":301679,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEr doping forms stable dual-wavelength emission and increases PL intensity.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e Time-dependent PL spectra of the typical CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3 \u003c/sub\u003emicroplate under the continuous laser excitation (wavelength 405 nm). \u003cstrong\u003eb\u003c/strong\u003e The Emission intensity of WBP and NBP CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3 \u003c/sub\u003eextracted from (a) as a function of time. \u003cstrong\u003ec\u003c/strong\u003e PL spectra of the typical CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate with light soaking time of 0s and 30s. \u003cstrong\u003ed\u003c/strong\u003e Schematic diagram of ion migration facilitated by dangling bonds on the surface. \u003cstrong\u003ee\u003c/strong\u003e Time-dependent PL spectra of the typical Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate under the continuous laser excitation (wavelength 405 nm). f The Emission intensity of WBP and NBP of Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3 \u003c/sub\u003eextracted from (e) as a function of time. \u003cstrong\u003eg\u003c/strong\u003e PL spectra of the typical Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate with light soaking time of 0s and 30s.\u003cstrong\u003e h\u003c/strong\u003e Schematic diagram of Er doping inhibition of ion migration.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/42d980cbcd337b79965b079c.png"},{"id":59273952,"identity":"6e687a5e-f306-4c8e-ae23-55dfbfd9aee4","added_by":"auto","created_at":"2024-06-28 13:31:51","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":490004,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLight-induced heterostructure of host perovskite and intrinsic heterostructure of Er-doped perovskite. a \u003c/strong\u003ePL spectrum of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate collected at position 1 and position 2 in inset optical image and PL mapping photograph collected and WBP and NBP. \u003cstrong\u003ec\u003c/strong\u003e PL spectrum of Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate collected at position 1 and position 2 in inset optical image and PL mapping photograph collected and WBP and NBP. \u003cstrong\u003eb and d\u003c/strong\u003e Schematic diagram of the formation of light-induced heterostructure in host perovskite and the formation of intrinsic heterostructure of Er-doped perovskite.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/65e4eddb9fc96348e41145ef.png"},{"id":59273955,"identity":"c0e3ef54-0ef7-47dd-857b-a78340bfbb01","added_by":"auto","created_at":"2024-06-28 13:31:51","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":410521,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSpatial and time-resolved PL characterization of Er:2%-CsPb(Br\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e0.77\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003eI\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e0.23\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e and a\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e Representative streak camera images of the time-resolved PL collected at 590 nm (WBP, \u003cstrong\u003ea\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e) and 660 nm (NBP,\u003cstrong\u003e a\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e). \u003cstrong\u003eb\u003c/strong\u003e PL decay curve extracted from (a), the illustration is the diagram of Ⅰ-type band arrangement. \u003cstrong\u003ec \u003c/strong\u003ethe lifetime statistics with increased light soaking time of WBP and NBP extracted from the streak camera images. \u003cstrong\u003ed\u003c/strong\u003e Representative spatial profiles of the NBP for 0 and 500 ps after pulsed excitation using a 650 nm bandpass filter to filter out the green light. \u003cstrong\u003ee\u003c/strong\u003e Carrier diffusion diagram of NBP. \u003cstrong\u003ef\u003c/strong\u003e Corresponding time-dependent variance σ(t)\u003csup\u003e 2\u003c/sup\u003e of the CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3 \u003c/sub\u003eand Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/b1a4ac0fcb564264ce66c5c8.png"},{"id":59273950,"identity":"a4470105-bb34-4480-9bb4-dbc6b7883509","added_by":"auto","created_at":"2024-06-28 13:31:51","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":105002,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEr concentration-dependent lifetime statistics and effects on ion migration rate.\u003c/strong\u003e \u003cstrong\u003ea \u003c/strong\u003eThe mean lifetime statistics of WBP\u003csub\u003e \u003c/sub\u003eof CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates with different Er\u003csup\u003e3+\u003c/sup\u003e doping concentrations as a function of light soaking time. \u003cstrong\u003eb\u003c/strong\u003e I\u003csub\u003eNBP\u003c/sub\u003e/I\u003csub\u003esat \u003c/sub\u003eof CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates with different Er\u003csup\u003e3+\u003c/sup\u003e doping concentrations as a function of light soaking time. \u003cstrong\u003ec\u003c/strong\u003e schematic diagram of two mechanisms existing in Er doping system.\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/12e22dc190739b25f2b736ba.png"},{"id":59274349,"identity":"70abfe62-3757-4fc8-a779-c970df6ce0ec","added_by":"auto","created_at":"2024-06-28 13:39:51","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":266868,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eModel diagram of Er doping forming intrinsic heterostructure and increasing PL intensity.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/92c218dbd82aaaeb57bcef97.png"},{"id":62434456,"identity":"1adc96a7-2a80-46ef-9953-0695cbb7cfa3","added_by":"auto","created_at":"2024-08-14 07:28:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2834044,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/2dab4be9-2d4a-4e9e-a6a4-e581ba7f3a31.pdf"},{"id":59273956,"identity":"72a78132-3cc8-44f0-a265-f684dbe28c0f","added_by":"auto","created_at":"2024-06-28 13:31:51","extension":"docx","order_by":8,"title":"","display":"","copyAsset":false,"role":"supplement","size":2083617,"visible":true,"origin":"","legend":"","description":"","filename":"SI.docx","url":"https://assets-eu.researchsquare.com/files/rs-4634105/v1/6701a86364cde12a54c390b8.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Stable Lateral Heterostructure in All-inorganic Perovskites with Suppressed Halide Ions Migration","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThree-dimensional (3D) metal halide perovskites (MHPs) composed of ABX\u003csub\u003e3\u003c/sub\u003e (A stands for monovalent metal cation such as Cs\u003csup\u003e+\u003c/sup\u003e, B is a divalent metal cation, X refers to halide anions)\u003csup\u003e1,2\u003c/sup\u003e crystallographic structure present a uniquely promising material for next-generation optoelectronic applications, such as solution-processed solar cells\u003csup\u003e3,4\u003c/sup\u003e, light-emitting diodes\u003csup\u003e5,6\u003c/sup\u003e, detectors and lasers\u003csup\u003e7\u0026ndash;9\u003c/sup\u003e. Although their inherently soft crystal lattice allows large tolerance to lattice mismatch\u003csup\u003e10\u0026ndash;13\u003c/sup\u003e, they also enable high intrinsic ion mobility due to the dangling bonds at the grain boundaries and surface defects. For this reason, mixed MHPs have been demonstrated to undergo a high ion migration velocity and a hysteresis effect under light illumination or an electric field, which degrade the performance of materials and signifies a challenge for commercialized optoelectronic devices\u003csup\u003e14\u003c/sup\u003e. Their high intrinsic ion mobility makes the epitaxial growth of atomically sharp heterostructures challenging because the ion diffusion usually leads to a large junction width\u003csup\u003e15,16,17\u003c/sup\u003e. More generally, it is challenging to prepare single-component halide heterostructures by one-step method due to the close preparation temperature between the different components. Due to this, the complicated two-step solution-based or chemical vapor deposition (CVD) method is usually used to prepare heterostructure MHPs, but some experimental studies have shown that these methods are more likely to form alloying phase perovskites rather than heterostructures perovskites\u003csup\u003e18\u0026ndash;20\u003c/sup\u003e. Therefore, the effective inhibition of ion migration in MHPs is necessary for the further preparation of single-component heterostructure perovskites.\u003c/p\u003e \u003cp\u003eVarious attempts to suppress this light-induced ion migration in mixed MHPs have been adopted, such as increasing the concentration of larger halogen ions or substituting A-site ions with small alkali metal cations\u003csup\u003e21\u0026ndash;24\u003c/sup\u003e. Besides, the B-site replacement, such as the incorporation of bivalent metal ions (Mn\u003csup\u003e2+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Sn\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e) and tervalent ions (Bi\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Yb\u003csup\u003e3+\u003c/sup\u003e), has also been considered as another promising avenue which could significantly improve the stability of MHPs and optimize the photophysical properties\u003csup\u003e25,26\u003c/sup\u003e. Among a variety of B-site dopants, the rare earth ion Er\u003csup\u003e3+\u003c/sup\u003e has been proven to promote the lattice distortion of perovskites octahedral frame due to heterovalent doping, and the shallow defect level between the valence band and conduction band could significantly improve the luminous intensity and color purity of MHPs\u003csup\u003e27,28\u003c/sup\u003e. More importantly, since the electrons in the 4f orbital are effectively shielded by the electrons in the outer 5s and 5p layers, Er\u003csup\u003e3+\u003c/sup\u003e doping can protect perovskites from the disturbance of the ambient temperature, which is an ideal dopant.\u003c/p\u003e \u003cp\u003eIn this work, Er-doped all-inorganic perovskite lateral heterostructure microplates, CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1\u0026minus;x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, were prepared by a simple one-step solution method. Both the ions migration inhabitation and the heterostructure formation mechanism were explored through photoluminescence (PL) spectroscopy and time-resolved PL (TRPL) spectroscopy. We proposed that Er\u003csup\u003e3+\u003c/sup\u003e is more inclined to combine with the larger size I\u003csup\u003e\u0026minus;\u003c/sup\u003e to form the ErI\u003csub\u003e5\u003c/sub\u003e polyhedron, while the Pb\u003csup\u003e2+\u003c/sup\u003e is preferred to combine with the smaller size Br\u003csup\u003e\u0026minus;\u003c/sup\u003e to form the PbBr\u003csub\u003e6\u003c/sub\u003e octahedra, thus promoting the formation of stable intrinsic heterostructure. Besides, Er doping relieved the lattice stress between the different halides and eliminated the dangling bonds at the grain boundaries, effectively increasing the ion migration barrier and radiation recombination efficiency. Therefore, the rapid movement of halogen ions was inhibited. The discoveries provide a basis for studying ion migration inhabitation mechanisms for MHP systems and a platform for optoelectronic devices with multiple emission channels, including multi-channel photodetectors, solar cells, and lasers\u003csup\u003e29\u003c/sup\u003e.\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003eThe one-step solution spin-coating method was used to prepare Er-doped CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates (Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e) by adding an Er(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e powder into the CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e reaction system (see Methods and Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e in Supporting Information). The Er concentrations in host perovskite were controlled by tuning the mole ratio of source materials. As schematically shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea, the Er\u003csup\u003e3+\u003c/sup\u003e dopants tend to occupy the B-site and replace the host Pb\u003csup\u003e2+\u003c/sup\u003e in the perovskites lattice \u003csup\u003e28\u003c/sup\u003e. The heterovalent doping of Er\u003csup\u003e3+\u003c/sup\u003e could distort the adjacent octahedrons and induce lattice distortion. The lattice structure of prepared Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates with different Er concentrations (0–5% in precursor solutions) was characterized by X-ray diffraction (XRD) tests, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb. As indicated from the diffraction peaks, all perovskites have cubic phase lattice structures (PDF#75–0412) with prominent Bragg diffraction peaks corresponding to (100), (110), and (200) planes\u003csup\u003e29\u003c/sup\u003e. With increasing the Er concentration, the (200) diffraction peak constantly exhibits a slight shift toward the larger angle (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec), suggesting a certain extent of lattice shrinkage. In our case, the observed lattice shrinkage is due to the Er\u003csup\u003e3+\u003c/sup\u003e with a small ionic radius (89 pm) replacing the larger host Pb\u003csup\u003e2+\u003c/sup\u003e (119 pm). Simultaneously, the Er doping could also induce the band gap expansion of MHPs perovskites, as manifested in the blue-shift of absorption spectra (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ed) caused by shrink lattice.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTo study the influence of the Er doping on the micromorphology and element distribution, scanning electron microscope (SEM) images and elemental mappings of typical Er:2%-CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate were conducted (Fig. e-j and Fig. S2). The SEM images indicate that both undoped and doped samples exhibit a square shape with a side length of ~ 3 µm (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee and h). It is worth noting that the distribution of I\u003csup\u003e−\u003c/sup\u003e is different in the host and doped samples (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eg and j). According to the Energy Dispersive X-ray (EDX) results, the Cs, Pb, Br, and I elements are uniformly distributed in the host microplate, and the estimated chemical formula for this sample is CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). According to EDX dot scan analysis, the Br/I ratio in the central (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee position 1) and the edge region (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee position 2) are closed, demonstrating the uniformity of the host sample. In the Er-doped sample, the Br/I ratio in the central region (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eh position 1) is 4.7:1, higher than the 3:1 of the outer region (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eh position 2) (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). These results imply that the Er-doped microplate tends to form a halogen heterogeneous structure, where more I\u003csup\u003e–\u003c/sup\u003e inclines to distribute at the edge region of the microplate than the central region, as schematically illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ek. It resembles a planar heterostructure with the narrow bandgap perovskites in the edge region and wide bandgap perovskites in the central region.\u003c/p\u003e \u003cp\u003eTo further explore the influence of Er-doping on the dealloying and ion migration characteristics, we carried out the PL spectral experiment under continuous light-soaking. A continuous wave laser with a wavelength of 405 nm was used as the soaking light source. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea and e show the pseudo-color images of PL spectra variation as a function of light-soaking time for the CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, respectively. A significant photoinduced phase separation is generated in the host perovskite. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea, the PL spectra exhibit a single alloying peak at ~ 590 nm at the initial soaking time (t = 0 s). Then, the peak intensity decreases quickly within 5 seconds of light-soaking time, and a new PL peak near 700 nm appears simultaneously. After 5 seconds of light-soaking, the PL intensity at 590 and 700 nm still maintains an opposite variation tendency with extending the light-soaking time but with a much slower intensity variation rate (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb and Fig.S3). During the photoexcitation, the more easily mobile I\u003csup\u003e−\u003c/sup\u003e migrates to the edge region of the microplate, resulting in a light-induced dealloying process. The structural formula of two segregated perovskites with different halide composition ratios was approximately CsPb(Br\u003csub\u003e0.75\u003c/sub\u003eI\u003csub\u003e0.25\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and CsPb(Br\u003csub\u003e0.3\u003c/sub\u003eI\u003csub\u003e0.7\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e as determined from their PL peak (The calculation procedure is shown in SI), which correspond to a wide bandgap phase (WBP) and a narrow bandgap phase (NBP), respectively. The ion migration rate of the NBP can be obtained by fitting the first-order rate constant K\u003csub\u003eforward\u003c/sub\u003e according to the following formula\u003csup\u003e30\u003c/sup\u003e:\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e\n$$\\frac{{I}_{NBP}}{{I}_{sat}}=1-{e}^{-{K}_{forward}t}$$\u003c/div\u003e \u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\u003c/div\u003e \u003cp\u003e\u003c/p\u003e \u003cp\u003ewhere I\u003csub\u003eNBP\u003c/sub\u003e is the PL intensity of NBP, and I\u003csub\u003esat\u003c/sub\u003e is the saturation emission intensity. According to the fitting results, the NBP has a fast ion migration rate with the K\u003csub\u003eforward\u003c/sub\u003e of 0.42 S\u003csup\u003e− 1\u003c/sup\u003e in the first 5 seconds of light-soaking and then decreases to 0.09 S\u003csup\u003e− 1\u003c/sup\u003e after 5 seconds. This rapid ion migration rate may come from the unbonded dangling bond on the surface of the single crystal microplate, which provides a path for the migration of I\u003csup\u003e−\u003c/sup\u003e, and the long carrier diffusion length of MHPs also provides a convenient condition for I\u003csup\u003e−\u003c/sup\u003e to move to the edge of the microplate (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed).\u003c/p\u003e \u003cp\u003eUnlike the host sample, the Er-doped microplate exhibits distinct dual-peak PL emission at 580 and 690 nm at the 0-second light-soaking time and maintains this dual PL peak during the recorded entire light-soaking (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee). The results imply that the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate exhibits intrinsic phase segregation even before the light-soaking. Unusually, the PL intensity of both NBP and WBP increases linearly with the extension of light-soaking time, but the PL rise rate of 690 nm is significantly higher than that of 580 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ef). The light-soaking here plays an essential role in suppressing the non-radiative recombination, which was also reported by \"photo-passivation.\" It can be speculated that the suppression of non-radiative recombination originates from the photoinduced defects repairing process\u003csup\u003e28\u003c/sup\u003e. Besides, with the incorporation of Er\u003csup\u003e3+\u003c/sup\u003e, shallow level defects, including Er 4f energy level, are introduced between the valence band and conduction band, thus reducing the difficulty of carrier transition and increasing the PL intensity\u003csup\u003e27\u003c/sup\u003e. The WBP and NBP were approximately determined as CsPb(Br\u003csub\u003e0.78\u003c/sub\u003eI\u003csub\u003e0.22\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and CsPb(Br\u003csub\u003e0.56\u003c/sub\u003eI\u003csub\u003e0.44\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, respectively (see Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eg and SI). According to the spectral characterization, the host perovskite undergoes an obvious ion migration process under light-soaking and realizes the evolution from a single alloy phase to two phases with different Br/I ratios (bandgap). After doping, Er\u003csup\u003e3+\u003c/sup\u003e in the host perovskite eliminates the dangling bond at grain boundry, reducing the ion migration channel. At the same time, lattice shrinkage and heterovalent doping caused by small size further promote the lattice distortion of the octahedron, increase the ion migration barrier, thus the ion migration is inhibited effectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh).\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea and c show the PL mappings of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates collected at WBP and NBP region, respectively. The PL mappings indicate that both the host and doped perovskite form the heterostructure, with WBP mainly distributed in the center and NBP distributed on the margin of the microplate. Although both PL mappings indicate similar mapping results, the heterostructure formation mechanism is significantly different. For the host MHPs, this heterostructure is a dynamic process induced by ion migration, producing a light-induced heterostructure (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb). The metastable uniform single alloy-phase perovskite is distributed on the surface of the microplate in dark conditions. Under light excitation, the I\u003csup\u003e−\u003c/sup\u003e continuously moved away from the alloy-phase perovskite which is located at the central area of the light excitation, and this process is a dynamic component separation process. The long carrier diffusion characteristics of MHPs enable I\u003csup\u003e−\u003c/sup\u003e to migrate to the edge of the microplate. As a result, a light-induced planer heterostructure in the host microplate is formed. For the Er-doped microplate, both elements mapping and PL results indicate the heterostructure is intrinsic before the photoexcitation. During the preparation process, a part of Er\u003csup\u003e3+\u003c/sup\u003e replaced Pb\u003csup\u003e2+\u003c/sup\u003e, resulting in lattice shrinkage and thus generating lattice stress in the MHP lattice. To eliminate this non-uniformity stress, during the annealing process, the Er\u003csup\u003e3+\u003c/sup\u003e preferentially coordinates with the large-sized I\u003csup\u003e−\u003c/sup\u003e to form a polyhedron with the longer Er-I bond, which could offset the lattice shrinkage caused by the small-sized B-site ions to a certain extent. As a result, more Br\u003csup\u003e−\u003c/sup\u003e are in the PbX\u003csub\u003e6\u003c/sub\u003e octahedron distributed at the center of the microplate, and more I\u003csup\u003e−\u003c/sup\u003e are in the ErX\u003csub\u003e5\u003c/sub\u003e polyhedron distributed on the edge, maintaining a stable state. Synthetically, the intrinsic heterostructure is formed (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ed).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eDue to the bandgap difference between the segregated MHP phase, the carriers at the heterointerface will migrate from the WBP to the NBP through a carrier funnel process\u003csup\u003e31\u003c/sup\u003e. A time-resolved photoluminescence (TRPL) experiment was employed to systematically investigate the heterostructure carrier dynamics and the effect of light-induced ion migration on the heterointerface during light-soaking. Using a femtosecond pulse laser with a wavelength of 400 nm to excite the entire sample, the streak camera images at the different light-soaking times were taken respectively, and the signal collection time was maintained 1 minute for each acquisition. As shown in Fig. S4, in the host CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate, the WBP exhibits a lifetime of 227 ps, while the NBP exhibits a longer PL lifetime of 547 ps. This result is consistent with the literature report, where I-rich perovskite has a greater dielectric constant compared with Br-rich perovskite, so the carriers have a strong shielding effect on defect impurities and reducing the radiation decay rate, resulting in a longer lifetime\u003csup\u003e32\u003c/sup\u003e. Figure\u0026nbsp;4a\u003csub\u003e1\u003c/sub\u003e and a\u003csub\u003e2\u003c/sub\u003e demonstrate the streak camera images from the WBP and NBP of the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate. The PL dynamic curves were extracted from these images and shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, where the WBP (580 nm) exhibits a PL rise time with a time constant of 10 ps and a single exponential PL decay with a lifetime of 538 ps, while NBP exhibits a prolonged PL rise time fitted by a single exponential decay with a lifetime of 649 ps. The rise time of the dynamic curve from the WBP can be found close to the instrument response function (IRF, ~ 10 ps). Differently, the rise time of the NBP is about 33 ps, which is much longer compared to the IRF. The prolonged rise time in the NBP section implies an extra energy inflow, which comes from the carriers' migration from the WBP to the NBP through a carrier funnel process\u003csup\u003e33\u003c/sup\u003e. The inset in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec designates the type-I band alignment diagram of the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate to elaborate the carriers' funnel process. The valence band (conduction band) of the WBP is lower (higher) than that of the NBP perovskite. The band offsets between the two different components could be regarded as an energy barrier to operate the NBP component, acts as an energy sink to capture the carriers from the high-energy WBP aided by large mixed perovskite diffusion lengths, thus converging the carriers at the low-energy region, then the PL intensity of the NBP continuously enhanced through radiation recombination.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec, the lifetimes of both WBP and NBP constantly increased with the increase of light-soaking time. This is significantly different from the undoped system, where the lifetimes of the WBP (NBP) demonstrate a continuous decrease (enhancement) due to the carrier funnel effect and ion migration (Fig. S4a and b). The lifetimes increasing can be expected in the Er-doping MHPs because when Er\u003csup\u003e3+\u003c/sup\u003e replaces Pb\u003csup\u003e2+\u003c/sup\u003e, the ionic bond in the MHPs crystal lattice will be strengthened, and the density of states in the conduction band increases, thus improving the static dielectric constant and reducing the surface defect. Additionally, the internal lattice defects will participate in the carrier recombination process due to the heterovalent doping of Er in the host perovskite, increasing the radiation recombination site and improving the lifetimes.\u003c/p\u003e \u003cp\u003eTo verify the intrinsic planar heterostructure in the Er-doped perovskite microplate, the diffusion behavior of carriers in the NBP region was studied using a spatial-resolved PL image, which was obtained by the streak camera (see experimental section). Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed indicates the carriers diffusion image from the NBP of the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate in the time scale of 0-500 ps. The PL intensity I\u003csub\u003ePL\u003c/sub\u003e(x,t) of the diffusion time-dependent spatial-resolved PL image could be well fitted by a Voigt function\u003csup\u003e34,35\u003c/sup\u003e:\u003c/p\u003e \u003cp\u003eI\u003csub\u003ePL\u003c/sub\u003e(\u003cem\u003ex, t\u003c/em\u003e)∝exp[− \u003cem\u003ex\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e/2σ(\u003cem\u003et\u003c/em\u003e)\u003csup\u003e2\u003c/sup\u003e] (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eΔσ\u003csup\u003e2\u003c/sup\u003e = σ\u003csup\u003e2\u003c/sup\u003e(t) − σ\u003csup\u003e2\u003c/sup\u003e(0) = 2Dt (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003csup\u003e36\u003c/sup\u003e\u003c/p\u003e \u003cp\u003ewhere \u003cem\u003ex\u003c/em\u003e is the one-dimensional spatial coordinate, \u003cem\u003eσ\u003c/em\u003e\u003csup\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sup\u003e \u003cem\u003e(t)\u003c/em\u003e and \u003cem\u003eΔσ\u003c/em\u003e\u003csup\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sup\u003e represent the variance of the carrier distribution as a function of time (t), and the mean-squared displacement describes the time evolution of space broadening, respectively. \u003cem\u003eD\u003c/em\u003e is the carrier diffusion coefficient, which can be obtained by Eq.\u0026nbsp;(3). As illustrated in the carriers diffusion profiles for the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate after the light excitation of 0 and 500 ps (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ee), the half-peak width of PL spectra at 500 ps shows a slight broadening compared to that at 0 ps, which confirms the carrier diffusion at the heterostructure interface. The \u003cem\u003eD\u003c/em\u003e value for the Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate is about 0.035 cm\u003csup\u003e2\u003c/sup\u003e/s, which is significantly reduced compared to that of the undoped sample, 0.07 cm\u003csup\u003e2\u003c/sup\u003e/s. According to Einstein's relation, the diffusion coefficient is proportional to mobility. It can be considered that Er doping inhibits the migration of carriers in NBP due to the lattice distortion caused by the substitution of trivalent ions for divalent. The reduced \u003cem\u003eD\u003c/em\u003e value also implies the prolonged radiative recombination lifetime and increased PL intensity, which is favorable for applying light-emitting devices.\u003c/p\u003e \u003cp\u003eAccording to the PL and TRPL spectral analysis above, there are two mechanisms of coexistence and competition in the Er-doped MHPs: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) the decrease of PL and lifetime of WBP caused by ion migration and (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) the increase of PL and lifetime caused by Er doping. To verify the assumption, we synthesized a series of MHP microplates with different Er concentrations to study the effects of varying dopant concentrations on lifetimes and ion migration rates. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea displays the light-soaking time-dependent lifetimes for WBP with five different Er concentrations (1%-5%). For each Er concentration, the average lifetime values were statistics analyzed from eight MHP samples (Table S3 to S7) and the lifetime value at each light-soaking time (1 to 8 min) are exhibited in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea. For Er concentrations of 1%, the average lifetime of WBP still declines with the extension of light-soaking time, which proves that ion migration is dominant in MHPs with low Er concentration (black curve in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea). When Er concentration exceeds 1%, the average lifetime of WBP perovskite increases gradually and reach a peak with the doping concentration is 3%, confirming the promotion of radiation recombination enabled by the addition of Er\u003csup\u003e3+\u003c/sup\u003e, and at this time the ion migration is at a disadvantage. When Er concentration continuously increases to 4% or 5%, the lifetime of WBP perovskite still exhibits an upward trend but with a slower speed because the excessive doping concentration will introduce more deep-level defects, resulting in the deterioration of perovskite performance. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eb exhibits a qualitative depiction of the relationship between PL intensity rise rate and Er concentration of NBP perovskite by plotting I\u003csub\u003eNBP\u003c/sub\u003e/I\u003csub\u003esat\u003c/sub\u003e as a function of light-soaking time (extracted from Fig. S5), where K is a valuable indicator to regulate the time evolution of PL intensity. Similar to the regularity of lifetime change, the K rises first with the increased Er concentration, from 0.0134 s\u003csup\u003e− 1\u003c/sup\u003e of Er:0% to 0.0372 s\u003csup\u003e− 1\u003c/sup\u003e of Er:3%. Then, the K value would reduced when the Er concentration is further increased due to excessive defects. Here, the PL intensity of the NBP is used for comparison to circumvent potential ambiguity and difficulty because when Er concentration is low (0%), the ion migration process dominates, and the PL intensity of WBP is gradually reduced, which is inconvenient for comparison. This process can also be explained by Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ec, that the ion migration plays a significant role when the Er doping concentration is low; in this situation, the carriers migrated from the WBP to the NBP by the carrier funnel effect, shortening the PL intensity and lifetime of WBP. With the increase of Er concentration, Er inhibits ion migration and promotes radiation recombination, contributing to the rise of PL and lifetime.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWe have confirmed that the lifetime of the WBP perovskite shows a time-dependent decay due to the dominant ion migration in the Er:1%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e sample (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea black curve). Some studies have reported that a small Br/I ratio could effectively inhibit ion migration. Therefore, we select perovskites with a smaller Br/I ratio of 3:2 and 2:3 (Er:1%-CsPb(Br\u003csub\u003e0.6\u003c/sub\u003eI\u003csub\u003e0.4\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er:1%-CsPb(Br\u003csub\u003e0.4\u003c/sub\u003eI\u003csub\u003e0.6\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e), which possesses inhibited ion migration rate than Er:1%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e for the comparative experiment. For both samples, the lifetime of WBP perovskite presents a time-dependent rise (Fig S6), which is undoubtedly different from Er:1%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, proving that the radiation recombination induced by Er doping is dominant after the inhibition of ion migration, it is further confirmed that these two mechanisms can be regulated. Both host and Er-doped perovskite thin films were prepared to verify the improved optical stability of Er-doped MHPs, and light-soaking time-dependent PL experiments were carried out (Fig. S7). The host perovskite film exhibits a rapid ion migration phenomenon, and the PL peak is continuously blue-shifted with the extension of the light-soaking time (Fig. S7a). Meanwhile, the PL peak shifted slightly for the Er-doped perovskite film, demonstrating the improved optical stability by Er doping (Fig. S7b). Additionally, the initial PL intensity of the Er-doped perovskite is much higher than that of the host perovskite (Fig. S7c), which further suggests that Er doping can not only improve the stability of the system by inhibiting ion migration but also increase the luminescence performance.\u003c/p\u003e \u003cp\u003eThe formation of heterostructure and PL mechanism of Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e is proposed in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e. The homogeneous alloy phase in the host CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate exhibits a light-induced spatially dealloying process, which is caused by migration and forms light-induced transient heterostructures. The light-soaking here activates the I\u003csup\u003e−\u003c/sup\u003e migration. Differently and interestingly, the Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate tends to form an intrinsic heterostructure that is not dependent on photoexcitation. It shows stable dual-wavelength emission in the spectra. The rule of the light-soaking in the Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e sample is light-induced shallow defect passivation and increased PL intensity.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eASSOCIATED CONTENT\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, Er-doped all-inorganic perovskite lateral heterostructure microplates, CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, were prepared by a simple one-step solution method. The Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e heterostructure microplate forms a stable dual-wavelength emission with enhanced PL intensity and lifetime. Compared to the undoped CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1−x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, the introduction of Er dopant into the perovskite effectively inhibits the ion migration and prompts the formation of the intrinsic heterostructure. Light-induced halide ions migration and luminescence enhancement caused by Er-deposited radiation recombination sites are exhibited simultaneously in the system. By optimizing the Er concentration and halogen ratio, ions migration and radiation recombination rate can be controlled to achieve an equilibrium. These results underline the basis for light-induced ion migration and pave the path for pursuing all inorganic perovskites with rare earth ion doping applied in multi-wavelength optoelectronic devices and commercially viable integrated circuits.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e \u003cem\u003ePreparation of microplates.\u003c/em\u003e Both CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e were prepared using a one-step solution coating method. For the synthesis of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, lead bromide (0.183 g, PbBr\u003csub\u003e2\u003c/sub\u003e, 99.99%, Aladdin), Cesium bromide (0.106 g, CsBr, 99.99%, Aladdin) were dissolved into 5 mL dimethyl sulfoxide (DMSO, AR, Macklin), then adding 1 mL deionized water and stirred for six hours at 323 K. Then, the moderate precursor solution was dripped onto the cleaned ITO substrate and spin-coated at 500 rpm for 30 s. Finally, put the substrate on the hot flake, annealing for 10 minutes at 393 K-473 K. For synthesizing Er-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, erbium nitrate (0.1 g, Er(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e, 99.99%, Mreda) was dissolved into 20 mL deionized water solution and stirred for six hours at 323 K. Then 0.5 g, 1 g, 1.5 g, 2 g, and 2.5 g of erbium nitrate precursor solution were dropped into CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e precursor, respectively, and continued stir for 6 hours to form solutions with different Er doping concentrations. The stirred precursor solution was repeated and annealed in the spin coating process.\u003c/p\u003e\u003cp\u003e \u003cem\u003ePL Spectra and Mapping Measurements.\u003c/em\u003e Steady-state PL spectra were detected by a confocal microscope system (WITec, alpha-300). The continuous laser at 405 nm was introduced to the confocal system and focused on the samples through the space light module through the charge-coupled device camera (DFK 23GV024) and an objective lens (50 ×, Zeiss, 0.75 numerical aperture). The in-situ PL signals were detected by a spectrometer (150 g/mm grating). PL mapping measurements were conducted by a 50-fold lens to focus on the center of the microplate, and a ~ 20×20 µm square frame was used to select the tested area to test the PL spectra of each point in the area and image. The integration time of the scan was 0.1s.\u003c/p\u003e\u003cp\u003e \u003cem\u003eTRPL and Carrier Diffusion Experiments.\u003c/em\u003e TRPL experiments of WBP and NBP were measured by using a confocal microscope (WITec, alpha-300) as the collection device; the PL signal was reflected into the streak camera (C10910, Hamamatsu) by Ag mirrors with 400 nm laser pulses (Ti: sapphire laser with a repetition rate of 80 MHz and a pulse width of 80 fs) as the exciting light. The 400 nm wavelength output light was produced by an 800 nm laser from a mode-locked oscillator (Tsunami 3941-X1BB, Spectra-Physics) positioned after a BBO crystal. The excitation light was focused onto the sample by an objective lens (50 ×, Zeiss, 0.75 numerical aperture) with a spot diameter of ∼3 µm from the top. The carrier diffusion experiment was also measured by introducing the PL signal into the streak camera (C10910, Hamamatsu) to measure the spatial resolution spectra. The NBG PL signal is collected by placing a 600 nm long wave pass filter in front of the streak camera light module, then setting the collection center wavelength in the test system at 0 µm to avoid splitting the light, then the spatial diffusion behavior of NBP's carriers were recorded by spatial-resolved mapping image.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAUTHOR INFORMATION\u003c/p\u003e\n\u003cp\u003eCorresponding Author\u003c/p\u003e\n\u003cp\u003eXiujuan Zhuang,\u0026nbsp;College of Semiconductors (College of Integrated Circuits),\u0026nbsp;Hunan University, China\u003c/p\u003e\n\u003cp\u003eEmail: [email protected]\u003c/p\u003e\n\u003cp\u003eAuthor Contributions\u003c/p\u003e\n\u003cp\u003eJunyu He carried out the conception of experimental ideas, the analysis of data, and the writing of the manuscript; Xiujuan Zhuang completed the verification of experimental data, the provision of ideas, and the revision of the manuscript;\u0026nbsp;Yang Li and Tongqing Sun performed the optical characterizations; Anshi Chu and Min Li completed the preparation of experimental reagents; All authors discussed the results and commented on the manuscript.\u003c/p\u003e\n\u003cp\u003eNotes\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing financial interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors are grateful to the National Natural Science Foundation of China (Nos. 61635001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSupporting Information\u003c/strong\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe contents of the supporting information are listed as follows:\u003c/p\u003e\n\u003cp\u003eFlow chart of perovskite preparation by solution spin coating; SEM image EDS mapping of typical CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate; EDX spectra of both microplate of position 1 and position 2 in figure 1e and h; I\u003csub\u003eNBP\u003c/sub\u003e/I\u003csub\u003esat\u0026nbsp;\u003c/sub\u003ecurve of Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate with different light soaking time; Time-resolved PL curves of the CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplate; Fitting results of the parameters of the dynamic curves in Figure 4b; Lifetime table of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u0026nbsp;\u003c/sub\u003ewith different\u003csub\u003e\u0026nbsp;\u003c/sub\u003eEr concentration; Time-dependent PL spectra of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e microplates with different Er concentrations; Time-dependent PL spectra and TRPL results of 1%-Er: CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1-x\u003c/sub\u003e)\u003csub\u003e3\u0026nbsp;\u003c/sub\u003ewith varies Br/I ratio; Time-dependent and steady-state PL spectrum of CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e and Er:2%-CsPb(Br\u003csub\u003e0.77\u003c/sub\u003eI\u003csub\u003e0.23\u003c/sub\u003e)\u003csub\u003e3\u0026nbsp;\u003c/sub\u003eperovskite\u003csub\u003e\u0026nbsp;\u003c/sub\u003efilms. \u0026nbsp; \u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGreen MA, Ho-Baillie A, Snaith HJ (2014) The emergence of perovskite solar cells. 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Light-Sci Appl 11:340\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"dual-wavelength emission, lateral epitaxial heterostructure, all-inorganics perovskite, rare earth doping, ion migration, energy funnel ","lastPublishedDoi":"10.21203/rs.3.rs-4634105/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4634105/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe dangling bonds and surface defects at the grain boundaries of three-dimensional (3D) perovskite provide convenient conditions for non-radiative recombination and ion migration, which degrades the stability of perovskite materials. Herein, we prepared single-component lateral epitaxial heterostructure perovskites using a one-step solution method by rare earth Er\u003csup\u003e3+\u003c/sup\u003e doping. Through photoluminescence (PL) and time-resolved PL spectroscopy, the erbium-doped CsPb(Br\u003csub\u003ex\u003c/sub\u003eI\u003csub\u003e1\u0026minus;x\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e heterostructure microplate forms a stable dual-wavelength emission with enhanced PL intensity and lifetime. We find that rare earth doping can effectively suppress ion migration by improving the ion migration barrier and facilitating the intrinsic stable heterostructure formation with desired dual-wavelength emission and improved radiation recombination rate. The discovery sheds a new perspective on inhibiting ion migration by trivalent B-site doping of rare earth ions and provides a basis for the preparation of single-component heterostructure perovskite.\u003c/p\u003e","manuscriptTitle":"Stable Lateral Heterostructure in All-inorganic Perovskites with Suppressed Halide Ions Migration","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-28 13:31:46","doi":"10.21203/rs.3.rs-4634105/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":"2ec0ac66-09c0-40f9-a9aa-c23e410e3f40","owner":[],"postedDate":"June 28th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":33788293,"name":"Physical sciences/Materials science/Materials for optics"},{"id":33788294,"name":"Physical sciences/Optics and photonics/Optical materials and structures"},{"id":33788295,"name":"Physical sciences/Optics and photonics/Optical physics"},{"id":33788296,"name":"Physical sciences/Optics and photonics/Optical techniques"}],"tags":[],"updatedAt":"2024-08-14T07:20:46+00:00","versionOfRecord":[],"versionCreatedAt":"2024-06-28 13:31:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4634105","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4634105","identity":"rs-4634105","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}