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Perovskite solar cells (PSCs) continue to be the "front runner" technology among emerging photovoltaic devices in terms of power conversion efficiency and versatility of applications. However, improving stability and understanding their relationship with their ionic–electronic transport mechanisms continue to be challenging. In this work, a case study of NiOx-based inverted PSCs and the effect of different interface passivating treatments on device performance is presented. Impedance spectroscopy (IS) measurements in short-circuit conditions were performed under different illumination intensities, as well as bias-stress operational stability tests under constant illumination intensity. Surface treatments that involved bulky Lewis bases resulted in better and more stable performance. In contrast, acidic anion donors could induce both an initial performance decrease with a characteristic three-arcs impedance Nyquist plot and a subsequent instability during light exposure. Drift–diffusion simulations suggest strong modifications of surface recombination at the interface with the hole transport material, and for the ion concentration and mobilities in the perovskite. Importantly, capacitance and resistance are shown to peak maximum and minimum values, respectively, around mobile ion concentration (Nion) of 1016 and 1017 cm−3. These features relate to the transition from a drift-, for low Nion below a threshold value, to a diffusion-dominated transport in the bulk of the perovskite, for high Nion beyond the threshold value. Our results introduce a general route for characterization of instability paths in PSCs via IS performed under short-circuit conditions. [ABSTRACT FROM AUTHOR]

Presented here is the optimization of a planar two-terminal perovskite/silicon tandem solar cell with a texture structure. The developed simulation model is fitted to published experimental results, and the importance of current matching in the two-terminal structure is discussed. With the texture structure optimized and considering current matching, the optimal texture structure improves J s c from 17.9 to 20.87 mA/cm 2 compared to the planar structure, as well as improving the power conversion efficiency from 25.8% to 35.9%. Furthermore, if the quality of the perovskite thin film and tunneling junction efficiency with a smaller voltage penalty can be improved, then the efficiency can be further improved to 38.13%. This indicates that this tandem solar cell still has much room for improvement. [ABSTRACT FROM AUTHOR]

This work investigated the influence of microwave sintering on the BaCe 0.2 Zr 0.7 Y 0.1 O 3-δ phase, incorporating 2 mol% or 4 mol% NiO as sintering aid. X-ray diffraction analysis of perovskite phase detected a rhombohedral structure under both sintering heating rates (280 and 500 °C/min), also exhibiting the presence of a second phase deficient in Ba with Ni incorporated into the structure, replacing part of the Zr. Raman analysis indicated no distortions in the perovskite structure, independent of the rates and NiO concentrations. The efficacy of NiO addition as a sintering aid was demonstrated by high densification of the samples, exceeding 97 % relative density. Detailed analysis of structural, microstructural, and conductivity properties revealed that microwave sintering, particularly using a heating rate of 500 °C/min, yielded superior results compared to conventional sintering. The enhanced electrical response was attributed to a higher concentration of structural defects, oxygen vacancies, in the microwave-sintered samples, evidenced by the band at 630 cm−1 in the Raman spectrum. Among these, the BCZY sample with 2 mol% NiO, sintered under these conditions, stood out as the most promising, showcasing not only high density but also a uniform microstructure and appreciable electrical conductivity. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) and lanthanum strontium manganite (LaSrMnO3) have been widely studied for various applications due to their amazing physicochemical properties. This work explains the influence of reduced graphene oxide in LaSrMnO3 perovskite, i.e., rGO@LaSrMnO3 nanocomposite for supercapacitor application. A facile combustion route was employed to synthesize rGO@LaSrMnO3 nanocomposites as promising electrode materials for supercapacitors. XRD analysis confirmed the perovskite structure of LaSrMnO3, while FESEM and EDAX revealed intimate interfacial contact between rGO nanosheets and LaSrMnO3 nanoparticles. BET measurements demonstrated a significant increase in surface area due to rGO incorporation, while FTIR spectroscopy confirmed the presence of oxygen vacancies. XPS analysis further corroborated the composite's reduced graphene oxide state and Mn3⁺ oxidation states. Consequently, the rGO@LaSrMnO3 (15R) electrode exhibited a remarkable specific capacitance of 1417.1 F/g at 1 A/g. This enhanced performance is attributed to the synergistic effect high electrical conductivity of rGO and the pseudocapacitive behavior of LaSrMnO3. This work presents a rapid and scalable approach for fabricating high-performance supercapacitor electrodes with improved capacitance and cyclability. [ABSTRACT FROM AUTHOR]

This work exposits a hybrid perovskite-based solar cell consisting of NiOx as an electron-blocking material and TiO2 as a hole-blocking material to enhance its performance. Because the EBL material is critical to increasing efficiency and stability in a perovskite-based photovoltaic device, NiOx is being taken as a blocking material for improved reliability. It is also cost-effective and shows less hysteresis in contrast with alternative EBL materials. In addition, a wide band gap material like TiO2 as HBL is considered for enhancing carrier transportation phenomena that improve device performance. The efficiency of the suggested photovoltaic device is assessed in terms of solar parameters using the TCAD numerical simulation tool, accounting for the impacts of the thickness of the perovskite material, the density of defects, and the blocking material doping concentration. Also, the temperature reliability study is thoroughly investigated, considering all the optimised thicknesses of different layers and their optimised doping level. [ABSTRACT FROM AUTHOR]

Scaling up perovskite solar cells stands as one of the frontiers in advancing this rapidly growing technology. Yet, controlling perovskite thin‐film crystallization during and post‐printing differs significantly from lab‐scale processes that have yielded record device efficiencies. This study investigates antisolvent treatment for slot‐die‐coated perovskite solar cells using in situ optical spectroscopy and comparing among multiple antisolvents. The antisolvent bath used in slot‐die coating affects the perovskite crystallization and film quality differently when comparing to the established spin‐coating antisolvent treatment process. A novel dynamic antisolvent method, employing either vortex or laminar flow, is developed. It outperforms steady‐bath techniques in generating high‐quality, haze‐free films. Optimization studies identify critical treatment times. Implementing this novel antisolvent treatment leads to a peak average power conversion efficiency of 15.62% and the highest device efficiency of 18.57%, an excellent performance for slot‐die‐coated MAPbI3 devices printed and tested under ambient conditions. The method is validated for an alternative perovskite composition, FA0.9Cs0.1PbI3, and printing technique, blade coating. This research highlights the importance of in situ analysis for enhancing perovskite film quality and introduces scalable approaches for controlling large‐area film crystallization kinetics, driven by the demand for efficient and scalable manufacturing processes in the field of perovskite solar cells. [ABSTRACT FROM AUTHOR]

Zirconium silicate (ZrSiO3) perovskite is a promising material for various technological applications. The structural, electronic, and thermodynamic properties of ZrSiO3 perovskite are studied under different conditions, including pressure and layer configuration variations using density functional theory. The present investigation includes a thorough analysis of 2D perovskite derivatives derived from its basic 3D structure. The bulk and surface‐terminated silicon‐dominant SiO2 and zirconium‐dominant ZrO compounds are found to be mechanically stable with an anisotropy factor above 1. The calculated indirect‐bandgap values for the ZrO termination and SiO2 termination are found to be 2.585 and 1.639 eV, respectively. Moreover, the pore size of the SiO2‐terminated slab model of ZrSiO3 is calculated to be 105.39 μm and that for ZrO‐termination to be 129.30 μm. Thus, the material considered for the study can have potential applications in bone regeneration and tissue engineering. Further, the possibilities for modifying ZrSiO3 for uses in electrical devices, sensors, sustainable energy materials, and even biomedical applications like tissue engineering are intriguingly expanded by the present findings. [ABSTRACT FROM AUTHOR]

Metal halide perovskites are crystalline materials with a sharp increase in popularity and rapidly becoming a major contender for optoelectronic device applications. In this work, we provide the optoelectronic features of a possible novel candidate, ZSnCl3 (Z = Na/K) Sn‐based on a detailed numerical simulation. The output of the current computations is compared to the results that are currently available, and a respectable agreement is noted. The studied compounds were cubic in nature and structurally stabe. The mechanical properties reflect the mechanical stability and ductility of the proposed materials. The Sn‐based single perovskite compounds proposed in this study are mechanically stable and ductile. The narrow direct band gap for NaSnCl3 and KSnCl3 are 1.36 eV and 1.47 eV, respectively, using the HSE06 hybrid function with the Boltztrp2 integrated in Quantum ESPRESSO (QE) software. The effective use of these compounds in perovskite solar cells and other optoelectronic applications was confirmed by optical absorption spectral measurements conducted in the photon energy range of 0–20 eV. [ABSTRACT FROM AUTHOR]

The structural, optoelectronic, and photovoltaic properties of CsPbIBr2 perovskite films were significantly enhanced by incorporating 4% Ni doping and utilizing a double electron transport layer (ETL) consisting of titanium dioxide (TiO2) and nickel-doped tungsten trioxide (Ni-WO3). X-ray diffraction (XRD) analysis of perovskite film revealed an increase in crystal size from 29.9 nm to 55.2 nm and a decrease in lattice constant from 6.024 Å to 6.012 Å upon Ni doping, indicating improved crystallinity. The energy bandgap of pure and Ni-CsPbIBr2 decreased from 2.0 eV to 1.94 eV, respectively, enhancing light absorption efficiency. The refractive index of pure and Ni-CsPbIBr2 increased from 2.625 to 2.645, respectively, enhancing light trapping and absorption. J–V measurements showed an efficiency increase from 12.26% to 12.96% with the introduction of a double ETL, demonstrating significant advancements in perovskite solar cell performance. [ABSTRACT FROM AUTHOR]

The free vibration analysis of a perovskite solar cell (PSC) within thermal environments is studied through a quasi-3D plate model. This model is designed to account for the stretching effects and non-uniform shear strains throughout the thickness. The PSC film is represented in the model as a thin laminated plate, comprising five distinct plies: ITO, PEDOT:PSS, perovskite, PCBM, and Au. A graphene platelets reinforced composite (GPLRC) substrate, made of Poly (methyl methacrylate), is assumed to be located under the noted five layers. The GPLRC substrate is conceptualized in the model as a porous foundation with finite depth. The foundation stiffnesses are determined using a modified Vlasov model, and the equivalent Young modulus of the foundation is evaluated using a modified Halpin–Tsai model, introducing the porosity coefficient. It is also considered that the material properties of GPLRC substrates exhibit temperature dependency. For the PSC with all edges simply supported, Navier solution method is applied to obtain the frequencies and associated mode numbers. Based on the results presented in this study, an increase in the porosity and thickness of the substrate can negatively impact the frequencies of the structure. However, natural frequencies experience almost no change if the temperature rises. [ABSTRACT FROM AUTHOR]

The current density–voltage characteristic (J–V) is a critical tool for understanding the behavior of solar cells. This study presents an overview of the key aspects of J–V analysis and introduces a user‐friendly flowchart that facilitates the swift identification of the most probable limiting process in a solar cell, based mainly on the outcomes of light‐intensity‐dependent J–V measurements. The flowchart is developed through extensive drift‐diffusion simulations and a rigorous review of the literature, with a specific focus on perovskite and organic solar cells. Moreover, the flowchart proposes supplementary experiments that can be conducted to obtain a more precise prediction of the primary performance losses. It therefore serves as an optimal starting point to analyse performance losses of solar cells. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have shown high optical absorption and consequently provide high conversion efficiency with stable performance. In our work, CH3NH3PbI3 (MAPbI3) as an absorber layer is analyzed for different crystalline structures. Cubic, tetragonal, and orthorhombic phases of perovskite material are investigated to check the impact of the crystalline structure on the solar cell performance. Both density of states and band structure are studied using Quantum-ESPRESSO package depending on density functional theory. Then, all relevant parameters were employed in SCAPS software and comprehensive study was done for examining the effect of the crystalline structure of perovskite layer on the solar cell performance. In-depth, analyses were conducted to evaluate key parameters, including open circuit voltage (Voc), short circuit current (Isc), fill factor (FF), and power conversion efficiency (PCE) considering the variations of perovskite layer thickness and bulk defect densities. The obtained results indicate that cells with cubic MAPbI3, which shows a notably higher bandgap of 1.7 eV and an enhanced optical absorption coefficient, especially in the higher wavelength range (around 105 cm−1), show better performance for almost all three scenarios. Cubic MAPbI3 cells achieve relatively higher peak efficiency of 26% when the absorber layer thickness is almost 900 nm. The investigation into absorber bulk defect densities reveals the critical role of defect levels in PSC performance. Adjusting defect levels from 1014 cm−3 to 1018 cm−3 results in deteriorating trends in Voc, Jsc, FF, and PCE. Jsc remains stable until a defect level of 1017 cm−3, highlighting a threshold where defects begin to impact charge carrier generation and separation. Doping effect has been studied, PCE remains stable until a critical doping level of 1016 cm−3 after which it drops significantly which indicates that doping is cautioned against due to its adverse effects on material and carrier transport. This finding holds significant promise for experimental solar cell fabrication, as it suggests that cubic MAPbI3's superior bandgap and enhanced optical absorption could lead to more efficient and robust photovoltaic devices in real-world applications. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have shown high optical absorption and consequently provide high conversion efficiency with stable performance. In our work, CH3NH3PbI3 (MAPbI3) as an absorber layer is analyzed for different crystalline structures. Cubic, tetragonal, and orthorhombic phases of perovskite material are investigated to check the impact of the crystalline structure on the solar cell performance. Both density of states and band structure are studied using Quantum-ESPRESSO package depending on density functional theory. Then, all relevant parameters were employed in SCAPS software and comprehensive study was done for examining the effect of the crystalline structure of perovskite layer on the solar cell performance. In-depth, analyses were conducted to evaluate key parameters, including open circuit voltage (Voc), short circuit current (Isc), fill factor (FF), and power conversion efficiency (PCE) considering the variations of perovskite layer thickness and bulk defect densities. The obtained results indicate that cells with cubic MAPbI3, which shows a notably higher bandgap of 1.7 eV and an enhanced optical absorption coefficient, especially in the higher wavelength range (around 105 cm−1), show better performance for almost all three scenarios. Cubic MAPbI3 cells achieve relatively higher peak efficiency of 26% when the absorber layer thickness is almost 900 nm. The investigation into absorber bulk defect densities reveals the critical role of defect levels in PSC performance. Adjusting defect levels from 1014 cm−3 to 1018 cm−3 results in deteriorating trends in Voc, Jsc, FF, and PCE. Jsc remains stable until a defect level of 1017 cm−3, highlighting a threshold where defects begin to impact charge carrier generation and separation. Doping effect has been studied, PCE remains stable until a critical doping level of 1016 cm−3 after which it drops significantly which indicates that doping is cautioned against due to its adverse effects on material and carrier transport. This finding holds significant promise for experimental solar cell fabrication, as it suggests that cubic MAPbI3's superior bandgap and enhanced optical absorption could lead to more efficient and robust photovoltaic devices in real-world applications. [ABSTRACT FROM AUTHOR]

The crystallization conditions from the solution play an important role in determining the morphology, phase composition, and photovoltaic properties of perovskite films. Post-processing of the obtained films can have a crucial role in increasing the grain size of perovskite and enhancing its crystallinity. It has been shown that the formation of crystal nuclei can be utilized to accelerate crystallization. In this case, crystallization occurs through the growth of seed crystals created in the solution, enabling the formation of relatively large crystals. For the deposition of CH3NH3PbI3 hybrid halide perovskite films from a solution of the perovskite in dimethylformamide, the spin coating technique was employed. Pre-crystallization was achieved by annealing the films at a temperature of 100 or 110 °C. The dissolution process involved adding a drop of dimethylformamide onto the substrate surface and allowing it to partially dissolve the perovskite film. Subsequently, residual solvent was removed through spin coating. The morphological analysis of the perovskite film surface after recrystallization at temperatures ranging from 80 to 130 °C was performed. The infrared transmission spectra of the obtained perovskite films were investigated, and their light absorption characteristics were studied through transmission spectra. The perovskite structure in the obtained films was confirmed by the peaks observed in the X-ray diffraction patterns. It has been shown that the photocurrent values for solar cells with perovskite films obtained by recrystallization are 15–20% higher than those of perovskite films obtained by traditional crystallization methods. [ABSTRACT FROM AUTHOR]

Multi-junction photovoltaics approaches are being explored to mitigate thermalization losses that occur in the absorption of high-energy photons. However, the design of tandem cells faces challenges such as light reflection and parasitic absorption. Nanostructures have emerged as promising solutions due to their anti-reflection properties, which enhances light absorption. III-V nanowires (NWs) solar cells can achieve strong power conversion efficiencies, offering the advantage of potentially integrating tunnel diodes within the same fabrication process. Metal halide perovskites (MHPs) have gained attention for their optoelectronic attributes and cost-effectiveness. Notably, both material classes allow for tunable bandgaps. This study explores the integration of MHPs with III-V NWs solar cells in both two-terminal and three-terminal configurations. Our primary focus lies in the optical analysis of a tandem design using III-V semiconductor nanowire arrays in combination with perovskites, highlighting their potential for tandem applications. The space offered by the compact footprint of NW arrays is used in an interpenetrated tandem structure. We systematically optimize the bottom cell, addressing reflectivity and parasitic absorption, and extend to a full tandem structure, considering experimentally feasible thicknesses. Simulation of a three-terminal structure highlights a potential increase in efficiency, decoupling the operating points of the subcells. The two-terminal analysis underscores the benefits of nanowires in reducing reflection and achieving a higher matched current between the top and the bottom cells. This research provides significant insights into NW tandem solar cell optics, enhancing our understanding of their potential to improve photovoltaic performance. [ABSTRACT FROM AUTHOR]

Perovskite oxides, with their diverse properties and versatile structures, have emerged as promising materials for electrochemical energy storage devices. The X‐ray diffraction patterns of both BaLaMnFeO6 (BLMFO), and its reduced graphene oxide (rGO) composite, synthesized through solvothermal process, revealed the formation of rhombohedral structure with space group R‐3C (no. 167). The estimated lattice parameter are a = 5.59 Å, b = 5.59 Å and c = 13.60 Å. As per the Brunauer–Emmett–Teller (BET) analysis, BLMFO/rGO composite (≈32.12 m2 g−1) exhibited a higher specific surface area than pristine BLMFO (≈11.85 m2 g−1), which has been attributed to the enhanced porosity resulted due to addition of rGO. The specific capacitance of pristine BLMFO and composite BLMFO/rGO is found to be 170.7 and 330.2 Fg−1, respectively, at the current density 1 Ag−1. The present investigation on the solvothermal synthesis and electrochemical analysis of BLMFO perovskite and its rGO composite, demonstrates potential for energy storage application. [ABSTRACT FROM AUTHOR]

Indoor applications for perovskite solar cells (PSCs) have achieved high power efficiency, which has attracted significant interest in the field of internet of things. Currently, the energy of typical indoor lights (color temperatures of 2700 K/3500 K/5000 K, irradiance of 1000 lx) are concentrated in visible range of 400–700 nm, which matches the band gap of CsPbI2Br perovskite (1.86 eV, cut-off at 670 nm). On the other hand, the fragile property of organic transport layers is difficult to keep the long-term stability of PSCs. Summarized bottlenecks we have mentioned above, multiple inorganic hole transport material (HTM) candidates in models of PSCs was introduced to obtain the highest efficiency through optimizing inorganic geometries. The results showed that the device with Cu2O-HTM exhibits the best performance at three color temperatures, which was attributed to the minimization of the energy difference between Au/HTL/PSK. In addition, by optimizing the hole mobility and doping density of HTL, defect density of the HTL/PSK interface, thickness of the perovskite, doping density and total defect density of the perovskite, thickness of ETL, electron mobility and doping density of HTL, defect density of PSK/ETL interface, our simulation can achieve high efficiencies of 34.02%, 32.67% and 31.51% at three color temperatures of 1000 lx light (2700 K, 3500 K and 5000 K). This research offers guidelines for constructing highly efficient PSCs with inorganic HTMs for experimental research under indoor light illumination. [ABSTRACT FROM AUTHOR]

Organic-inorganic heterojunction perovskite solar cells (PSCs) are of high interest due to their low manufacturing cost and higher power conversion efficiency (PCE). Hence, we study the opto-electro-thermal (OET) characteristics and investigate the optical and carrier transport and thermodynamic behaviors on the PSC. In this research, optical and electrical coupled behavior is investigated, and the results of this simulation are in the optimal state for nanoparticles (NPs) with a diameter of 50 nm: the short-circuit current ( J sc ) of 18.05 mA/cm2, the open-circuit voltage ( V oc ) of 0.9406 V, and PCE of 14.15% were obtained. Then, by adding thermal behavior to optical and electrical physics, thermal effects and power losses in the solar cell were obtained. In this case, 221.5 W/m2 Joule heat, 154 W/m2 thermal heat, 123 W/m2 Peltier heat, and 92.3 W/m2 nonradiative heat waste power were achieved. Under these losses, the electrical parameters decrease. The parameters are J sc = 21.74 mA/cm2, V oc = 0.94 V, and PCE = 13.53 %. The best case is obtained for the structure without NPs. [ABSTRACT FROM AUTHOR]

Optimally enhancing the performance of perovskite silicon tandem solar cells comes with accurate identification of loss origins in the device in combination with optoelectrical device simulations assessing the respective efficiency gains to prioritize optimization pathways. Herein, various characterization methods, namely, spectrally resolved photoluminescence (PL), transient-PL, PL-based implied opencircuit voltage (iVOC) imaging, spectrometric characterization, and Suns-VOC measurements are combined to quantify current density-voltage (jV) photovoltaic metric losses of a fully-textured perovskite silicon tandem solar cell (26.7% efficiency). The extracted device characteristic parameters are then used as a reference for the comprehensive optoelectrical Sentaurus simulation model which precisely reproduces the experimentally obtained optical and electrical solar cell characteristics, considering mobile ion dynamics. Subsequently, starting from the current device design, the authors alleviate one step at a time the loss constraints and show the impact of each loss channel on the efficiency, identifying the three major ones to be at the: 1) perovskite/C60 interface (-4.6%abs), 2) the series resistance (-2.9%abs), and 3) light management (-2.1%abs), which limit the VOC, fill factor, and jSC of the device, respectively. Furthermore, it is demonstrated that a practical efficiency potential of 39.5% can be regarded as a practical limit for the presented tandem device architecture. [ABSTRACT FROM AUTHOR]

While perovskite solar cells have reached competitive efficiency values during the last decade, stability issues remain a critical challenge to be addressed for pushing this technology towards commercialisation. In this study, we analyse a large homogeneous dataset of Maximum Power Point Tracking (MPPT) operational ageing data that we collected with a custom-built High-throughput Ageing System in the past 3 years. In total, 2,245 MPPT ageing curves are analysed which were obtained under controlled conditions (continuous illumination, controlled temperature and atmosphere) from devices comprising various lead-halide perovskite absorbers, charge selective layers, contact layers, and architectures. In a high-level statistical analysis, we find a correlation between the maximum reached power conversion efficiency (PCE) and the relative PCE loss observed after 150-hours of ageing, with more efficient cells statistically also showing higher stability. Additionally, using the unsupervised machine learning method self-organising map, we cluster this dataset based on the degradation curve shapes. We find a correlation between the frequency of particular shapes of degradation curves and the maximum reached PCE. Stability issues remain a critical challenge for perovskite solar cells towards commercialisation. Here, the authors analyse a large homogeneous dataset of Maximum Power Point Tracking operational ageing data and find a correlation between maximum power conversion efficiency and its relative loss. [ABSTRACT FROM AUTHOR]

The aim of this work is to investigate the degradation of perovskite solar cells (PSCs) by means of impedance spectroscopy, a highly sensitive characterization technique used to establish the electrical response of a device in a nondestructive manner. In this paper, PSCs with two different electron transport layers (ETLs) are studied: PSCs with undoped SnO2 as an ETL are compared to PSCs with an ETL composed of graphene-doped SnO2 (G-SnO2). Experimental data were collected immediately after fabrication and after one week, monitoring both impedance spectroscopy and dark current-voltage (I-V) curves. It was observed that, in the case of the undoped PSCs, the degradation of the solar cells affected both the AC behavior of the devices, modifying the associated Nyquist plots, and the DC behavior, observable from the dark I-V measurements. Conversely, the solar cells with G-SnO2 showed no variation. Considering the Nyquist plots, a quantitative analysis was performed by comparing the parameters of a proper equivalent circuit model. The results were coherent with those achieved in the DC analysis, thus proving that the analysis of impedance spectra, supported with dark I-V curves, allows one to gain a deeper knowledge of the degradation phenomena of perovskite solar cells. This study opens the door for further improvement of these devices through a better understanding of their electrical behavior. [ABSTRACT FROM AUTHOR]

Accurate structure analysis of epitaxial perovskite thin films is a fundamental step towards the ability to tune their physical properties as desired. Precession-assisted electron diffraction tomography (PEDT) has proven to be an effective technique for performing ab initio structure solutions and refinements for this class of materials. As the film thickness or the region of interest (ROI) decrease in size, the capacity to collect PEDT data with smaller electron beams is a key parameter and ROI tracking becomes a major issue. To circumvent this problem, we considered here an alternative approach to acquiring data by combining PEDT with a scan over an area, extracting the intensities collected at different positions and using them to perform accurate structure refinements. As a proof of concept, a Scanning Precession Electron Tomography (SPET) experiment is performed on a 35 nm thick perovskite P r V O 3 (PVO) film deposited on a S r T i O 3 (STO) substrate. This way, it was possible to detect small changes in the PVO structure along the film thickness, from the variation in unit cell parameters to atomic positions. We believe that SPET has the potential to become the standard procedure for the accurate structure analysis of ROIs as small as 10 nm. [ABSTRACT FROM AUTHOR]

[Display omitted] • JV curves show how MABr improves long-term performance. • EQE and EIS show the physical origin of the improvement. • MABr permits the formation of benefic photoactive phases. In this study, perovskite solar cells with a structure Cs y FA 1-x MA x CS 0.05 Pb(I 1.05-x Br x) 3 , with X = 0 (no doping was added to the base structure CsFAPbI 3) and X = 0.085 (CsFAPbI 3 was doped with 8.5% MABr 3) were prepared and were subjected to a 60 days ageing process (15 days under vacuum conditions followed by 45 days under room conditions) to study their stability. J-V curves showed that after the 60 days, the cells with no MABr3 only had 50.32% of the original efficiency remaining, while the samples with 8.5% MABr 3 had 92.89% of the original efficiency, being the J sc the main parameter that was affected during the ageing period. IPCE measurements suggest the formation of Cs segregates, that maintain or even increase the J sc. According to electrochemical impedance studies, these segregates could be promoted by the lower ionic movement resistance in the 8.5% MABr 3 samples, which may allow to re-arrange the atoms of the crystalline structure in a benefic way. This work is of great importance because it helps to understand how the doping affects the degradation processes, while showing how Impedance Spectroscopy can be used to characterize the changes in the electrical and ionic dynamics of the solar cells. [ABSTRACT FROM AUTHOR]

Perovskite materials have gained considerable attention in recent years for their potential to improve the efficiency of solar cells. This study focuses on optimizing the efficiency of perovskite solar cells (PSCs) by investigating the thickness of the methylammonium-free absorber layer in the device structure. In the study we used a SCAPS-1D simulator to analyze the performance of MASnI3 and CsPbI3-based PSCs under AM1.5 illumination. The simulation involved using Spiro-OMeTAD as a hole transport layer (HTL) and ZnO as the electron transport layer (ETL) in the PSC structure. The results indicate that optimizing the thickness of the absorber layer can significantly increase the efficiency of PSCs. The precise bandgap values of the materials were set to 1.3 eV and 1.7 eV. In the study we also investigated the maximum thicknesses of the HTL, MASnI3, CsPbI3, and the ETL for the device structures, which were determined to be 100 nm, 600 nm, 800 nm, and 100 nm, respectively. The improvement techniques used in this study resulted in a high power-conversion efficiency (PCE) of 22.86% due to a higher value of VOC for the CsPbI3-based PSC structure. The findings of this study demonstrate the potential of perovskite materials as absorber layers in solar cells. It also provides insights into improving the efficiency of PSCs, which is crucial for advancing the development of cost-effective and efficient solar energy systems. Overall, this study provides valuable information for the future development of more efficient solar cell technologies. [ABSTRACT FROM AUTHOR]

The perovskite solar cell (PSC) is one of the most burgeoning astronautic photovoltaic candidates with intrinsic microscales in thickness. One of the key concerns for the PSC within its operating status is nonlinear dynamic performance owing to ultra-thin structural attributes and dynamic impacts. This paper explores the size-dependent nonlinear dynamic behavior of the PSC under blast impacts. A multi-scale nonlinear dynamics framework is developed based on the modified strain gradient theory, extending the analytical nonlinear response analysis to microscale composites. Considering the von-Kármán geometric nonlinearity, the size-dependent motion equations are derived, and can be subsequently resolved by the fourth-order Runge–Kutta method to assess the transient response and blast impact resistance of the PSC. Diverse effects of the microplate theories, material length scale parameters, structural geometry, elastic foundations, damping, and blast impulses on the size-dependent nonlinear dynamic characteristics are systematically examined. Concluding remarks from the present study will be beneficial to the astronautic design and space deployment of the PSC energy harvesting devices with improved impact carrying capacity and safety. [ABSTRACT FROM AUTHOR]

In this work, a Mn-and Yb-doped BaTiO3-(Na0.5Bi0.5)TiO3 ferroelectric relaxor was designed and prepared. The effects of Mn on the microstructures, dielectric and electrical properties of the ceramics were investigated. The X-ray structural analysis shows a perovskite structure. The SEM images show the homogeneous microstructure of ceramics with an average grain size of about 1 μm. The temperature-dependent permittivity shows relaxor characteristics as Mn-doped. Mn at a low level (x ≤ 0.005) is beneficial for low dielectric loss and high resistivity. The maximum resistivity of ≥3 × 1012 Ω cm and minimum dielectric loss of ≤0.06 can be achieved at x ≤ 0.005. The resistivity of the ceramics follows the Arrhenius law with activation energy decreasing from ~1.31 to 1.01 eV as x increases. With lower Mn dopant, oxygen vacancies and charge carrier concentration partially decrease with Mn doping, which is helpful to improve the insulation resistance and decrease the dielectric loss. [ABSTRACT FROM AUTHOR]

The external quantum efficiency (EQE) of state‐of‐the‐art near‐infrared perovskite light‐emitting diodes (PeLEDs) is now approaching the limit set by the out‐coupling efficiency. However, there is plenty of room for enhancing these devices' radiance and the EQE roll‐off. This work reports how conductive and passivating additives construct efficient high‐radiance near‐infrared PeLEDs with improved EQE roll‐off. Specifically, the synergistic effect of 1,4‐phenylenediacetic acid (PDA) and 5‐aminovaleric acid (5‐AVA) is used to regulate the quality of the perovskite emissive layer, thereby enhancing the roll‐off threshold of injection currents (a value at which the device EQE or radiance starts degrading). According to in situ structural evolution analyses from the perovskite precursor to the perovskite crystal, the presence of PDA within the perovskite precursor solution can produce an intermediate phase with 5‐AVA and formanmidinium cation, which can retard the perovskite nucleation and crystal growth, leading to improved perovskite film quality. The resulting champion PeLED delivers among the highest radiance of 505 W sr−1 m−2 and a peak EQE of 17.56%. More importantly, the improved PeLED shows a well‐retained radiance of 80% at a current injection density of up to ≈1800 mA cm−1, opening a new avenue for high‐radiance PeLEDs with improved roll‐off degradation. [ABSTRACT FROM AUTHOR]

Herein, perovskite solar cells are fabricated and tested in underwater conditions in the laboratory. The fabricated perovskite solar cell (PSC) shows an efficiency of 14.29% outside water. It demonstrates an impressive power density of 10.49 and 11.88 mW cm−2 at a depth of 10 cm in seawater and deionized (DI) water environment, respectively. Compared with commercial silicon solar cells, PSCs are less affected by the water depth level due to their wide bandgap. The quantum efficiency measurement studies show that the perovskite solar cell is quite unaffected over the 400–800 nm wavelength in underwater environment. On the other hand, the spectral response of silicon solar cell is significantly hampered in the infrared region (700–1050 nm) due to light absorption by water. Absorption peaks of water correspond to the observed dips in quantum efficiency spectra of solar cells, indicating that light absorption due to water is primarily responsible for the decrease in photocurrent and electrical performance in underwater conditions. [ABSTRACT FROM AUTHOR]

Organic and perovskite semiconductor materials are considered an interesting combination thanks to their similar processing technologies and band gap tunability. Here, we present the design and analysis of perovskite/organic tandem solar cells (TSCs) by using a full optoelectronic simulator (SETFOS). A wide band gap lead-free ASnI2Br perovskite top subcell is utilized in conjunction with a narrow band gap DPPEZnP-TBO:PC61BM heterojunction organic bottom subcell to form the tandem configuration. The top and bottom cells were designed according to previous experimental work keeping the same materials and physical parameters. The calibration of the two cells regarding simulation and experimental data shows very good agreement, implying the validation of the simulation process. Accordingly, the two cells are combined to develop a 2T tandem cell. Further, upon optimizing the thickness of the front and rear subcells, a current matching condition is satisfied for which the proposed perovskite/organic TSC achieves an efficiency of 13.32%, Jsc of 13.74 mA/cm2, and Voc of 1.486 V. On the other hand, when optimizing the tandem by utilizing full optoelectronic simulation, the tandem shows a higher efficiency of about 14%, although it achieves a decreased Jsc of 12.27 mA/cm2. The study shows that the efficiency can be further improved when concurrently optimizing the various tandem layers by global optimization routines. Furthermore, the impact of defects is demonstrated to highlight other possible routes to improve efficiency. The current simulation study can provide a physical understanding and potential directions for further efficiency improvement for lead-free perovskite/organic TSC. [ABSTRACT FROM AUTHOR]

A myriad of studies and strategies have already been devoted to improving the stability of perovskite films; however, the role of the different perovskite crystal facets in stability is still unknown. Here, we reveal the underlying mechanisms of facet-dependent degradation of formamidinium lead iodide (FAPbI3) films. We show that the (100) facet is substantially more vulnerable to moisture-induced degradation than the (111) facet. With combined experimental and theoretical studies, the degradation mechanisms are revealed; a strong water adhesion following an elongated lead-iodine (Pb-I) bond distance is observed, which leads to a d-phase transition on the (100) facet. Through engineering, a higher surface fraction of the (111) facet can be achieved, and the (111)-dominated crystalline FAPbI3 films show exceptional stability against moisture. Our findings elucidate unknown facet-dependent degradation mechanisms and kinetics. [ABSTRACT FROM AUTHOR]

Low‐dimensional additive engineering could effectively reduce the high‐density trap defect density and improve the stability of perovskite solar cells (PSCs). To avoid the limiting effect of charge carrier transfer by incorporating the large‐size long alkyl chain organic cations, we developed a new three‐dimensional organic spacer cation, 1,4‐diazabicyclo [2,2,2] octane‐1,4‐diium (DABCO2+), to passivate the defects and enhance the device stability. DABCO2+ with fine crystal structure and thermal stability could result in substantially fewer structural defects, enhance carrier lifetime, and inhibit nonradiative recombination loss. Structural analysis of CsFAPbI3 perovskite doped with different concentrations of the three‐dimensional organic spacer cations shows a clear correlation between the structure and the resultant perovskite films. Consequently, DABCO2+ modified CsFAPbI3‐based PSCs could achieve an optimized PCE of 23.02% with high stability exceeding 1500 h. This work opens a new approach to fabricating PSCs with enhanced stability for future commercial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Toluene conversion rate exceeds 93 % and the H 2 production reaches 0.436L/g toluene. • The regulation of chemical properties is more effective for toluene cracking. • Material structure–activity relationship is quantified by heatmap analysis. • O2– is the most critical for catalytic cracking of toluene to produce H 2. • Partial oxidation reaction is critical to the hydrogen production process. The catalytic cracking of tar can be efficiently converted into syngas and further processed into liquid fuels and chemicals, thereby reducing pipe blockage and resource waste, which has attracted significant interest. In this study, LaFe 0.5 Ni 0.5 O 3 perovskites was synthesized using five different methods, and their structure–activity relationships were investigated deeply. The results showed the 27 material properties of the five perovskite catalysts were significantly different, and the potential reasons for these differences in properties were analyzed in detail. Most importantly, the mutual influence among the physical, chemical, and catalytic performance of the catalysts was quantitatively evaluated through heat map analysis. The most critical physical and chemical properties of materials for toluene conversion and hydrogen production were identified. Tafel slope (TS, 0.97), hydrogen consumption for the reduction of high-valent metals (Area α , 0.96), material impedance (R 2 , 0.93), and surface lattice oxygen content O2– (0.77) were key properties for toluene conversion. The progress of intermediate reaction was validated as the rate-limiting stage of toluene cracking. The Enhancement of surface lattice oxygen in chalcogenides can effectively promote toluene cleavage for hydrogen production, which was attributed to the partial oxidation reaction of toluene. Adjusting chemical properties improved toluene conversion rate and H 2 production more effectively and directly than physical properties. LFNO-SG exhibited significant promise for converting tar into hydrogen-rich syngas. [ABSTRACT FROM AUTHOR]

Lanthanum ferrite (LaFeO 3) is a potential candidate for Perovskite Solar Cell (PSC) application. The transition metal oxide has strong electron-electron correlation which results in an increase in quantum efficiency (QE) of PSC. In this investigation, we reported synthesis of LaFeO 3 perovskite material, simulation of LaFeO 3 -based PSC followed by experimental validation. The sol-gel method was employed to prepare nanoparticles of LaFeO 3 for PSC application. The prepared perovskite material is analyzed by XRD, SEM, EDS, UV–Vis and FTIR. The photovoltaic (PV) application of synthesized LaFeO 3 material is studied by SCAPS-1D. The LaFeO 3 -based PSC is simulated with various ETLs such as TiO 2 , PCBM, IGZO, In 2 O 3 , C 60, ZnO, SnO 2 , WS 2 and HTLs of Cu 2 O, CuInSe 2 , Spiro-OMeTAD, P3HT, D-PBTTT-14, V 2 O 5 , CFTS, CBTS. The simulation outcomes of 64 distinct configurations deduced the eight-best performing PSCs. For these eight PSCs, impact of thickness of perovskite absorber layer, operating temperature, defect density, series and shunt resistance, work function of back contact, J-V characteristics and QE curve has been studied. We have achieved theoretical maximum efficiency of 13.03 % for the configuration of FTO/WS 2 /LaFeO 3 /CBTS/Au. The optimized structure has experimentally obtained maximum efficiency of 0.79 %. This shows that it is promising material for future PV application. • LaFeO 3 perovskite material has been synthesized by using sol-gel method. • The calculated optical E g is approximately 2.3 eV. • The average particle size of synthesized perovskite material is ∼80 nm. • The study of LaFeO 3 -based PSC with various electron transport layers and hole transport layers using SCAPS-1D software. • The LaFeO 3 -based PSC has achieved a maximum PCE of 0.79 % (experimentally) and 13.03 % (theoretically). [ABSTRACT FROM AUTHOR]

Two terminal (2T) perovskite/copper-indium-gallium-selenide (CIGS) tandem solar cells combine high conversion efficiency with lightweight flexible substrates which can decrease manufacturing and installation costs. In order to improve the power conversion efficiency of these tandem solar cells, the use of advanced simulation tools is crucial to estimate the loss mechanisms. In this regard, most of the available simulation works on tandem solar cells are oriented to minimize optical losses and assuming simplifications for the electrical simulations in particular in the top and bottom cell interconnection at the so-called tunnel recombination junction (TRJ) neglecting the inner physics of the complete tandem device. Therefore, the effect of charge exchange mechanism between top and bottom soler cells on the external parameters of a tandem devices is not fully understood yet. In this work, we present an experimentally validated opto-electrical model based on the fundamental semiconductor equations for the study of loss mechanisms of a reference perovskite/CIGS solar cell. Different from other numerical works, because our simulation platform includes the fundamental working mechanisms of the layers comprising the TRJ, we can properly calculate the losses related to it. We firstly present the calibration and validation of our opto-electrical model with respect to three fabricated reference solar cells: top cell only, bottom cell only and tandem device. Then, we use the calibrated model to evaluate main loss mechanisms affecting the baseline tandem device. Finally, we use the model to propose a roadmap for the optimization of monolithic perovskite/CIGS tandem solar cells. • Advanced opto-electrical modelling based in GenPro4 and TCAD Sentaurus of a baseline perovskite/CIGS tandem solar cell. • Simulations consistently couple optical, electrical models and charge transport mechanisms at tunnel recombination junction. • Loss analysis of the reference perovskite/CIGS tandem solar cell. • A roadmap for the optimization of monolithic perovskite/CIGS tandem solar cells. • Efficiency limit calculated at 26.69 % using a commercially available CIGS bottom solar cell. [ABSTRACT FROM AUTHOR]

Linoleic acid (LA) detection and edible oils discrimination are essential for food safety. Recently, CsPbBr 3 @SiO 2 heterostructures have been widely applied in edible oil assays, while deep insights into solvent effects on their structure and performance are often overlooked. Based on the suitable polarity and viscosity of cyclohexane, we prepared CsPbBr 3 @SiO 2 Janus nanoparticles (JNPs) with high stability in edible oil and fast halogen-exchange (FHE) efficiency with oleylammonium iodide (OLAI). LA is selectively oxidized by lipoxidase to yield hydroxylated derivative (oxLA) capable of reacting with OLAI, thereby bridging LA content to naked-eye fluorescence color changes through the anti-FHE reaction. The established method for LA in edible oils exhibited consistent results with GC–MS analysis (p > 0.05). Since the LA content difference between edible oils, we further utilized chemometrics to accurately distinguish (100%) the species of edible oils. Overall, such elaborated CsPbBr 3 @SiO 2 JNPs enable a refreshing strategy for edible oil discrimination. CsPbBr 3 @SiO 2 Janus nanoparticles (JNPs) with high oil stability and fast halide exchange (FHE) activity are finely prepared under solvent regulation. Through catalysis and redox reactions, linoleic acid (LA) is expressed as stable iodine molecules, exhibiting anti-FHE characteristics against JNPs. Accordingly, LA assay and edible oil species discrimination have been realized visually, showcasing the potential of perovskite in food analysis. [Display omitted] • Uniform CsPbBr 3 @SiO 2 Janus nanoparticles (JNPs) are tuned and prepared in cyclohexane. • JNPs exhibit high stability and fast halogen exchange (FHE) activity in edible oil. • Enzymatic anti-FHE enable linoleic acid assay and edible oil species discrimination. [ABSTRACT FROM AUTHOR]

Co-existence of different surfaces in traditional polycrystalline heterogeneous catalysts imposes a challenge to induce different kinds of catalytic species and average reactivity. Supported metal/oxide model catalyst designed with equivalent well-defined surfaces and active species provides an opportunity to control the uniformity, maintain efficient activity, and understand catalytic mechanisms at the atomic and molecular levels. Herein, sub-20 nm perovskite-structure BaTiO 3 polyhedron nanocuboids and Zr-substituted rhombic dodecahedron nanocrystals were synthesized and employed as the oxide support for the subsequent uniform growth of 1–2 nm Pt nanoparticles. These Pt nanoparticles were well dispersed on the 12 equivalent (110) facets of BaTi 0.75 Zr 0.25 O 3 rhombic dodecahedra and on the 6 equivalent (100) facets of BaTiO 3 nanocuboids. The main active centers on the Pt/BaTi 0.75 Zr 0.25 O 3 catalysts in the oxidized surface layer of Pt (111) facets are Pt4+ versus Pt2+, which is in contrast to the oxidized surface layer of the Pt (100) facets on the Pt/BaTiO 3 cuboids where there are a greater number of Pt2+ species. Compared with Pt/BaTiO 3 nanocuboids, the Pt/BaTi 0.75 Zr 0.25 O 3 catalysts demonstrated higher CO catalytic oxidation activity with a lower apparent Arrhenius activation energy. This work advances our ability to synthesize metal/oxide model catalyst that offer equivalent facets and highly uniform active centers with reasonable surface area in order to gain insight in reaction mechanisms. [Display omitted] • Synthesis of sub-20 nm perovskite nanocubes and rhombic dodecahedra. • HRTEM/STEM image analysis for perovskite oxide and 1–2 nm Pt nanoparticles. • CO oxidation and DRIFTS characterization on two supported Pt catalysts. • XPS characterization for Pt4+ and Pt2+ active species dispersion analysis. [ABSTRACT FROM AUTHOR]

In recent years, energetic molecular perovskites, which serve as an energetic material design platform, have shown potential for designing primary and secondary explosives. To explore their potential in gunpowder and pyrotechnics, this study constructed a new nitrate-bridged molecular perovskite, (H2dabco)[K(NO3)3] (DAN-2, H2dabco2þ = 1,4-diazabicyclo-[2.2.2.]octane-1,4-diium), based on potassium nitrate--a major component of black powder. The single-crystal structure analysis indicated that DAN-2 possesses a cubic perovskite structure in the space group Pm 3 m. Theoretical calculations revealed that DAN-2 has an energy level slightly higher than TNT and much higher than black powder. Adding DAN-2 into a typical propellant formulation can increase the impetus while significantly lowering the flame temperature. Moreover, DAN-2 has a lower sensitivity (IS = 29 J, FS > 360 N) than TNT (IS = 15 J, FS = 360 N). It is worth mentioning that DAN-2 can avoid the environmental concern of sulfide-induced acid rain since it does not bear any sulfur. Therefore, DAN-2 can be considered a new single explosive and a modern edition of black powder obtained via mixing oxidative KNO3 and a reductive organic fuel at the molecular scale. Furthermore, it displays promising potential in the field of gunpowder and pyrotechnics. [ABSTRACT FROM AUTHOR]

The performance of quasi‐2D perovskite light‐emitting devices (PeLEDs) has been greatly improved in the past several years. Characterizations such as transient absorption (TA) spectroscopy and absorption spectra have been widely adopted to confirm the phases in the quasi‐2D perovskite layers. However, all the above‐mentioned characterization techniques could only identify the n values of phases without providing information on the distribution of phases. Here, phase distributions on the quasi‐2D perovskite surfaces are identified by utilizing the charging effect during the scanning electron microscope (SEM) measurement. Then, compositional and antisolvent engineering are adopted to improve the quality of quasi‐2D perovskite films. Green PeLEDs with an external quantum efficiency (EQE) of >20% are achieved with more uniform condensed film morphology and proper phase distribution. The work shows that SEM measurement is a powerful tool for studying the phase distribution on the quasi‐2D perovskite surfaces. [ABSTRACT FROM AUTHOR]

In recent years, there has been a dynamic development of photovoltaic materials based on perovskite structures. Solar cells based on perovskite materials are characterised by a relatively high price/performance ratio. Achieving stability at elevated temperatures has remained one of the greatest challenges in the perovskite solar cell research community. However, significant progress in this field has been made by utilising different compositional engineering routes for the fabrication of perovskite semiconductors such as triple cation-based perovskite structures. In this work, a new approach for the rapid analysis of the changes occurring in time in perovskite structures was developed. We implemented a quick and inexpensive method of estimating the ageing of perovskite structures based on an express diagnosis of light reflection in the near-infrared region. The possibility of using optical reflectance in the NIR range (900–1700 nm) to observe the ageing of perovskite structures over time was investigated, and changes in optical reflectance spectra of original perovskite solar cell structures during one month after PSC production were monitored. The ratio of characteristic pikes in the reflection spectra was determined, and statistical analysis by the two-dimensional correlation spectroscopy (2D-COS) method was performed. This method allowed correctly detecting critical points in thermal ageing over time. [ABSTRACT FROM AUTHOR]

The effect of sintering temperature (Ts) on the phase formation, structural, multiferroic, and magnetoelectric properties of BaTi0.975Fe0.025O3 (BTFO) ceramics has been investigated. The samples have been prepared via a solid-state reaction route and sintered at various temperatures between 1200 °C and 1350 °C. Detailed X-ray diffraction (XRD) analysis confirms a perovskite structure with a tetragonal phase except for the samples sintered at 1350 °C where coexistence of tetragonal and hexagonal phase is observed. The hexagonal phase of the BTFO sample sintered at 1350 °C degrades the electrical properties. All compositions exhibit ferromagnetic behavior, as seen from the M-H curves. Magnetodielectric coefficient (MD) and Magnetoelectric (ME) voltage coefficient α ME have been measured to confirm the intrinsic magnetoelectric behavior. [ABSTRACT FROM AUTHOR]

A new design of perovskite solar cells (PSCs) with non-peripherally substituted octahexylphthalocyanine (C6PcH2) hole transporting material (HTM) and MoOx buffer layer was introduced through experiment and simulation analysis. The external quantum efficiency (EQE) and current density–voltage (JV) characteristics were performed to analyze the photovoltaic performance of the PSCs based on C6PcH2 HTMs. The EQE was over 73% within the visible region (at 450 nm) but lower at 740 nm due to parasitic light absorption of C6PcH2 molecules. As a result, a short-circuit current density (Jsc) Jsc = 16.3 mA/cm2, open-circuit voltage (Voc) Voc = 0.95 V, fill factor (FF) FF = 35%, and a power conversion efficiency PCE = 5.4% were recorded under reverse bias scans (from open-circuit to short-circuit). Simulation analysis with Silvaco and SCAPS-1D was also performed to support the carrier transport analysis of PSCs with C6PcH2 HTM as well their photovoltaic performance in temperature range from 303 to 258 K, in which the charge carrier mobility of C6PcH2 molecules were strongly improved. By reducing the temperature from 303 to 258 K, the simulated PCE of 19.6% was achieved for the PSCs utilizing C6PcH2 as an HTM. The difference in PCEs between the synthesized and simulated devices was in part due to the alignment of C6PcH2 molecules in thin film. The simulation results closely supported the experiment and promised an improved performance upon realizing unknown electro-optical semiconductor properties of the C6PcH2 layer. [ABSTRACT FROM AUTHOR]

• La 1-x Sr x Co 1-y Fe y O 3 perovskite-type oxides are renowned for their remarkable mixed ionic-electronic conductivity. • We synthesized single-phase La 0.5 Sr 0.5 Co 0.8 Fe 0.2-x Al x O 3-δ (x = 0–0.20) perovskite oxides via solution combustion. • Introducing trivalent aluminum (Al3+) into perovskite B-site enhanced redox stability and mitigated oxygen variations. • Al-substitution significantly influenced surface morphology, oxygen nonstoichiometry, and electrical conductivity. • Oxygen nonstoichiometry significantly influenced oxygen transport parameters, resulting in improved D chem and K chem at 900 °C for these perovskites. In recent years, there has been a surge in the investigation of perovskite-type complex oxides, with a particular focus on La 1-x Sr x Co 1-y Fe y O 3 , renowned for their exceptional mixed ionic-electronic conducting (MIEC) properties. La 0.6 Sr 0.4 Co 1-y Fe y O 3 compositions have prominently emerged in this research domain. The hypothesis of enhancing redox stability and mitigating oxygen variations by incorporating trivalent aluminum (Al3+) into the B-site of perovskite structures has gained attention. In this study, single-phase La 0.5 Sr 0.5 Co 0.8 Fe 0.2-x Al x O 3-δ (x = 0–0.20) perovskite oxides were synthesized using the solution combustion technique. The physicochemical properties of the synthesized materials were thoroughly characterized, including their morphology, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) analysis, oxygen nonstoichiometry, and electrical transport properties. Results revealed lattice parameter variations associated with oxygen nonstoichiometry and B-site cation size, exhibiting a decline up to x = 0.10 followed by an increase. Al-substitution significantly influenced surface morphology, oxygen nonstoichiometry, and electrical conductivity. Notably, La 0.5 Sr 0.5 Co 0.8 Fe 0.1 Al 0.1 O 3-δ displayed lower electrical conductivity (676 S cm−1 at 300 °C) among the studied oxides. Oxygen nonstoichiometry had a significant impact on oxygen transport parameters, with these perovskites demonstrating improved chemical diffusion coefficient, D chem (5.5 × 10-5 cm2 s−1), and the oxygen surface exchange coefficient, K chem (2.32 × 10-5 cm s−1) at 900 °C, suggesting its potential as an oxygen transport membrane. These findings underscore the promising role of Al-substituted perovskite oxides in various advanced applications. [ABSTRACT FROM AUTHOR]

In the family of perovskite materials, perovskite oxide gained considerable attention from researchers in diverse fields, due to their flexible chemistry. Here, cubic perovskite oxide AgNbO 3 was studied using DFT via CASTEP code, to explore the key properties under varying stress conditions ranging from 0 to 100 GPa. Phase stability was confirmed by XRD analysis. Electronic properties confirmed the increasing trend in the band gap from 1.422 eV to 1.722 eV, with increasing stress. Optical characteristics reveal high absorption, conductivity, and lower loss function. Significantly, the elastic constants (C 11 , C 12 , and C 44) satisfy the Born-stability criteria, ensuring the mechanical stability of the considered compound. Moreover, the Poisson ratio, Pugh's ratio (B/G), Frantsevich ratio, Cauchy pressure (P C), and anisotropic factor ensure the ductile nature as well as an anisotropic character over the entire stress range. The positive trajectory in phonon density confirms the thermal stability. Thermodynamically, the studied material shows high-temperature stability with a higher value of applied stress as confirmed by Debye temperature (θ D). Furthermore, an inverse association of enthalpy and total entropy with free energy was observed. Based on these findings, confidently suggested that the considered cubic perovskite oxide, AgNbO 3 , can be efficiently used for photovoltaic and high-temperature applications. [ABSTRACT FROM AUTHOR]

This study explores the influence of varying sintering temperatures on the structural, optical, electrical, and leakage current features of La 2 NiTiO 6 (LNTO), a double perovskite material synthesized through the citrate auto-ignition method. The X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray (EDX) analysis were employed to investigate the structure, microstructure, and compositional distribution of the samples. The samples sintered at various temperatures showed the monoclinic structure with space group P2 1 /n and were confirmed by Rietveld's refinement of the XRD patterns. The average grain size increased with higher sintering temperatures, which is consistent with the particle size estimated from the histogram plot of the FE-SEM data. The UV–visible (UV–Vis) spectroscopy showed that the energy band gap decreased as sintering temperatures increased. Impedance spectroscopy analysis revealed non-Debye type relaxation of charge carriers and confirmed the negative temperature coefficient of resistance (NTCR) behavior. Electrical analysis affirmed that the direct current (DC) conductivity is thermally activated, following the Arrhenius equation with an inverse temperature dependency. As the sintering temperature increases, the leakage current density decreases, and the leakage current conforms to the ohmic conduction mechanism. • Single-phase La 2 NiTiO 6 was prepared through the sol-gel citrate auto-ignition method. • Non-Debye type relaxation and NTCR behaviour were observed. • Activation energy decreased with the increase of sintering temperatures. • Scaling shows that the mechanism is temperature-independent. • Leakage current follows the ohmic conduction mechanism. [ABSTRACT FROM AUTHOR]

In this study, we investigate the temperature dependence of iodine vacancies in the organic-inorganic hybrid perovskite C H 3 N H 3 Pb I 3 through theoretical analysis. Iodine vacancies, as point defects, play a crucial role in the instability of perovskite solar cells. By employing molecular dynamics (MD) simulations, we calculate the formation energy of vacancies and examine its relationship with temperature. Our results reveal that the formation energy remains constant irrespective of temperature. However, elevated temperatures facilitate the provision of energy necessary for vacancy formation. To accurately determine the vacancy concentration, it is essential to consider the associated entropy changes. Analytical methods are employed to assess these entropy changes, offering valuable insights into the vacancy formation process. Utilizing the derived values, we quantify the concentration of vacancies and analyze their dependence on temperature. The findings obtained from this research contribute significant insights into the behavior of iodine vacancies within the studied C H 3 N H 3 Pb I 3 perovskite system. [ABSTRACT FROM AUTHOR]

Lead free polycrystalline (1-x)BZT-xBSCT ceramics with x = 0.45, 0.50 and 0.55 were prepared by solid state reaction method. The samples were sintered at 1325 °C. XRD analysis confirms the perovskite structure in all the samples. The average grain size of ceramics decreases from 7.38 to 5.36 μm with the increase in the BSCT content. A maximum value of ε equal to 5715 at room temperature was found for sample with x = 0.50 and all the samples show diffused phase transition. PE loops were recorded at different temperatures to understand the ferroelectric nature. The polarization extension mechanism was found in sample with x = 0.50 through Arrott curves. The results show that the properties in solid solution of Sm3+ modified BCT ceramics with BZT, which makes the prepared ceramics as the potential candidates for several applications. • Lead free Sm3+ modified (1-x)BZT-xBSCT ceramics with x = 0.45, 0.50 and 0.55 were prepared by solid state reaction route. • Dielectric and ferroelectric properties near Morphotropic phase boundary 'MPB' in Sm3+ Modified BZT-BCT Ceramics. • Power law described the diffusiveness of phase transition in paraelectric phase. • The values of Power law fitted parameter γ at 10 kHz lie between 1.85 to 1.92, which shows a high degree diffused phase transitions. • Maximum value of room temperature dielectric constant (ε = 5715) was found for sample with x = 0.50. • Arrott curves between "P2 vs E/P" confirms the polarization extension mechanism in sample with x = 0.50. [ABSTRACT FROM AUTHOR]

The physical properties of perovskites—the central components of perovskite solar cells (PSCs)—are crucial for photovoltaic (PV) performance. Suitable doping of perovskites can improve the electric-field distribution within them, thus enhancing their PV performance. In this study, the effects of the three doping strategies on PV performance of MAPbI 3 based PSCs were explored. First, uniform acceptor doping of perovskite was performed. With increasing uniform acceptor doping concentration (N A), the open-circuit voltage (V OC) gradually increased, but the short-circuit current density (J SC) decreased. As the decline in J SC limited further PCE increase, non-uniform acceptor doping of perovskite was performed, which increased the width of the space-charge region near the MAPbI 3 /SnO 2 interface, promoting the flow of holes from MAPbI 3 to the carbon electrode. The J SC increased from 19.05 to 22.30 mA cm−2, and the power conversion efficiency (PCE) increased from 19.74 % to 22.72 % when the doping concentration curve for non-uniform acceptor doping was a line passing through 3 × 1018 and 3 × 1014. In order to further enhance the PCE, simultaneous non-uniform acceptor doping and uniform donor doping of perovskite was adopted, which further improved the J SC and fill factor (FF), and the PCE increased from 22.72 % to 23.92 % when the uniform donor doping concentration was 1 × 1018 cm−3. This work provides a strategy of doping of perovskite for highly efficient PSCs. • The influence of electric field inside the PSCs on the PV performance was systematically investigated. • Non-uniform acceptor doping can effectively improve the short-circuit current density. • The PCE increases from 22.72 % to 23.92 % through formation of non–uniform doping p-n junction. [ABSTRACT FROM AUTHOR]

As lead-free halide perovskite material has favourable applications toward solar cells and renewable energy resources. This paper aims to study the optoelectronic, thermoelectric and mechanical behaviour of novel compound Cs 2 CuAsX 6 (X = Cl, Br, I) in the framework of density functional theory using wien2k code. To check crystal and thermodynamical stability, we investigated the lattice constant (a o), tolerance factor (t f) and formation energy (ΔH f) of Halide Double Perovskites (HDPs). Band structure calculation performs by PBE-GGA potential reveals the indirect and narrow band gaps, which have been further verified using TB-mBJ approach and obtained values are (1.03, 0.92, 0.6) eV for Cs 2 CuAsCl 6 , Cs 2 CuAsBr 6 , and Cs 2 CuAsI 6 , respectively. Furthermore, the investigation of the maximum optical conductivity within the energy range of 1.0–4.0 eV has demonstrated that the examined Double Perovskites (DPs) hold great potential for application in optoelectronic and photovoltaic devices. The semi-classical Boltzmann theory is employed for thermoelectric property calculation and Seebeck values along with electrical conductivity confirm the good figure of merits. Cs 2 CuAsI 6 has the highest ZT of the DPs that were examined, which is noteworthy. Also, Cs 2 CuAsI 6 is mechanically stable and shows ductile nature of material. [ABSTRACT FROM AUTHOR]

Amongst the different perovskites being investigated for application in solar cells, one of the most frequently scrutinized is methylammonium lead iodide CH3NH3PbI3 (or MAPbI3), which is usually obtained by the reaction of lead iodide (PbI2) with methylammonium iodide (MAI). Although this perovskite has been extensively studied and utilized in the manufacture of high-efficiency solar cells, its formation chemistry is still not well understood. Reliable experimental determination of the activation energy between PbI2 and MAI has been difficult due to the rapid reaction at room temperature. In this work, we determined the activation energy by adopting the Arrhenius equation. This was possible by controlling the reaction using MAI vapor, instead of liquid solution. This procedure allowed the reaction to be carried out at temperatures of up to 150 °C. The formation of MAPbI3 films was obtained by a two-step process: deposition of thin PbI2 film by thermal evaporation and subsequent conversion into perovskite by exposure to MAI vapor. The conversion of PbI2 to MAPbI3 as a function of temperature was probed by X-ray diffraction. An activation energy of 0.12 ± 0.02 eV was obtained. This low value explains the ease of MAPbI3 formation at low temperatures, and partially explains its instability in environmental conditions. [ABSTRACT FROM AUTHOR]

A dataset containing 599 data points from 146 publications on 2D/3D perovskite solar cells is analyzed using machine learning. The predictive models are developed for power conversion efficiency (PCE) using eXtreme Gradient Boosting regression, random forest regression and artificial neural networks while association rule mining is used to analyze the stability data to identify the descriptors leading to high stability 2D/3D cells. A predictive model is also developed for the bandgap to predict the missing values in the dataset for the use in PCE predictions. Models for both bandgap and PCE predictions are quite successful. The thickness of inorganic layer (n), radius of anion (Rx), and 2D cation (Rm) are found to be the most important descriptors for bandgap predictions; n and Rm, together with the bandgap, are found to be deterministic for PCE in regular cells while the bandgap, n, and conduction band energy of hole transport layer are the most influential descriptors in inverted structures. Association rule mining analysis for the stability indicates that the cells with layered perovskite structures are more stable while the 2D and 3D cations leading to the most stable cells are found to be butylammonium and formamidinium‐Cs mixed cation respectively. [ABSTRACT FROM AUTHOR]