Effect of Various Electron and Hole Transport Layers on the Performance of CsPbI3-Based Perovskite Solar Cells: A Numerical Investigation in DFT, SCAPS-1D, and wxAMPS Frameworks

Device modeling of high performance and eco-friendly FAMASnI 3 based perovskite solar cell

Developing environmentally friendly and highly efficient inverted perovskite solar cells (PSCs) encounters significant challenges, specifically the potential toxicity and degradation of thin films in hybrid organic-inorganic photovoltaics (PV). We employed theoretical design strategies that produce hysteresis-reduced, efficient, and stable PSCs based on composition and interface engineering. The devices include a mixed-organic-cation perovskite formamidinium methylammonium tin iodide ( FAMASnI 3 ) as an absorber layer and zinc oxide (ZnO) together with a passivation film phenyl-C61-butyric acid methyl ester (PC 61 BM ) as a double-electron transport layer (DETL). Furthermore, a nickel oxide (NiO) layer and a trap-free junction copper iodide (CuI) are used as a double-hole transport layer (DHTL). The optoelectronic characterization measurements were carried out to understand the physical mechanisms that govern the operation of the devices. The high power conversion efficiencies (PCEs) of 24.27% and 23.50% were achieved in 1D and 2D simulations, respectively. This study illustrates that composition and interface engineering enable eco-friendly perovskite solar cells, improving performance and advancing clean energy.

Numerical simulation to optimize power conversion efficiency of an FTO/GO/Cs2AgBiBr6/Cu2O solar cell

Efficient conversion of solar power to electrical power through the development of smart, reliable, and environmentally friendly materials is a key focus for the next-generation renewable energy sector. The involvement of degradable and toxic elements present in hybrid perovskites presents serious concerns regarding the commercial viability of these materials for the solar cell industry. In this study, a solar cell with a stable, nondegradable, and lead-free halide-based double perovskite Cs2AgBiBr6 as the absorber layer, Cu2O as a hole transport layer, and GO as the electron transport layer has been simulated using SCAPS 1D. The thickness of the absorber, electron transport, and hole transport layers are tuned to optimize the performance of the designed solar cell. Notably, perovskite solar cells functioned most efficiently with an electron affinity value of 4.0 eV for Cu2O. In addition, the effect of variation of series resistance and temperature on generation and recombination rates, current density, and quantum efficiency has been elaborated in detail. The findings of this study provide valuable insight and encouragement toward the realization of a non-toxic, inorganic perovskite solar device and will be a significant step forward in addressing environmental concerns associated with perovskite solar cell technology.

Optimizing Transport Carrier Free All-Polymer Solar Cells for Indoor Applications: TCAD Simulation under White LED Illumination

This work inspects the utilization of all-polymer solar cells (APSCs) in indoor applications under LED illumination, with a focus on boosting efficiency through simulation-based design. The study employs a SCAPS TCAD device simulator to investigate the performance of APSCs under white LED illumination at 1000 lux, with a power density of 0.305 mW/cm2. Initially, the simulator is validated against experimental results obtained from a fabricated cell utilizing CD1:PBN-21 as an absorber blend and PEDOT:PSS as a hole transportation layer (HTL), where the initial measured efficiency is 16.75%. The simulation study includes an examination of both inverted and conventional cell structures. In the conventional structure, where no electron transportation layer (ETL) is present, various materials are evaluated for their suitability as the HTL. NiO emerges as the most promising HTL material, demonstrating the potential to achieve an efficiency exceeding 27%. Conversely, in the inverted configuration without an HTL, the study explores different ETL materials to engineer the band alignment at the interface. Among the materials investigated, ZnS emerges as the optimal choice, recording an efficiency of approximately 33%. In order to reveal the efficiency limitations of these devices, the interface and bulk defects are concurrently investigated. The findings of this study underscore the significance of careful material selection and structural design in optimizing the performance of APSCs for indoor applications.

Mixed cations tin-germanium perovskite: A promising approach for enhanced solar cell applications

Significant progress has been made over the years to improve the stability and efficiency of rapidly evolving tin-based perovskite solar cells (PSCs). One powerful approach to enhance the performance of these PSCs is through compositional engineering techniques, specifically by incorporating a mixed cation system at the A-site and B-site structure of the tin perovskite. These approaches will pave the way for unlocking the full potential of tin-based PSCs. Therefore, in this study, a theoretical investigation of mixed A-cations (FA, MA, EA, Cs) with a tin-germanium-based PSC was presented. The crystal structure distortion and optoelectronic properties were estimated. SCAPS 1-D simulations were employed to predict the photovoltaic performance of the optimized tin-germanium material using different electron transport layers (ETLs), hole transport layers (HTLs), active layer thicknesses, and cell temperatures. Our findings reveal that EA0.5Cs0.5Sn0.5Ge0.5I3 has a nearly cubic structure (t = 0.99) and a theoretical bandgap within the maximum Shockley-Queisser limit (1.34 eV). The overall cell performance is also improved by optimizing the perovskite layer thickness to 1200 nm, and it exhibits remarkable stability as the temperature increases. The short-circuit current density (Jsc) remains consistent around 33.7 mA/cm2, and the open-circuit voltage (Voc) is well-maintained above 1 V by utilizing FTO as the conductive layer, ZnO as the ETL, Cu2O as the HTL, and Au as the metal back contact. This configuration also achieves a high fill factor ranging from 87 % to 88 %, with the highest power conversion efficiency (PCE) of 31.49 % at 293 K. This research contributes to the advancement of tin-germanium perovskite materials for a wide range of optoelectronic applications.

Numerical study of copper antimony sulphide (CuSbS2) solar cell by SCAPS-1D

Copper antimony sulphide thin films are promising, less toxic, and more absorbent material in the world, and they would be good to be applied in photovoltaic energy production. To better operations of copper antimony sulphide (CuSbS2) photovoltaic cells, this paper uses a solar cell capacitance simulator (SCAPS-1D) to simulate and analyze photovoltaic properties. This article examines different thicknesses of fluorine-doped tin oxide (FTO), cadmium sulphide (CdS), carbon (C), and CuSbS2, as well as the defect and dopant concentration in the CuSbS2 photoactive layer of the photovoltaic cell structure glass/FTO/n-CdS/p-CuSbS2/C/Au. Optimum thicknesses of CuSbS2 is 300 nm, carbon hole transport layer (HTL) is 50 nm, and for n-CdS electron transport layer (ETL) is 100 nm, giving open circuit Voltage (Voc) of 0.9389 V, short circuit current density (Jsc) of 28.32 mA/cm2, fill factor (FF) of 60.8% and solar cell efficiency of 16.17%. The increase in defects causes a decrease of carrier lifetime resulting in to decrease in diffusion length and the optimum absorber layer doping concentration was found to be 1018 cm-3.

Mathematical Modeling and Optimization of Highly Efficient Nontoxic All-Inorganic CsSnGeI3-Based Perovskite Solar Cells with Oxide and Kesterite Charge Transport Layers

Despite exceptional optoelectronic properties and rapidly increasing efficiency of perovskite solar cells (PSCs), the issues of toxicity and device instability have hampered the commercialization of this renewable energy technology. Lead (Pb) being the main culprit creates major environmental risks and therefore must be replaced with a nontoxic material such as tin (Sn), germanium (Ge), etc. Moreover, replacing organic cations in the perovskite's ABX3 structure with inorganic ones like cesium (Cs) helps aid the stability issues. This study uses six different kesterite-based hole transport layers (HTLs) and three different metal oxide-based electron transport layers (ETLs) to numerically simulate and optimize all-inorganic CsSnGeI3 PSCs. Metal oxide ETLs are used in this study due to their large band gap, while kesterite HTLs are used due to their excellent conductive properties. All of the simulations are performed under standard testing conditions. A total of 18 novel planar (n-i-p) PSCs are modeled by the combination of various charge transport layers (CTLs), and the device optimization was done to enhance the power conversion efficiencies (PCEs) of the PSCs. Furthermore, the effect of CTLs on the energy band alignment, electric field, quantum efficiency, light absorption, and recombination rate is analyzed. Additionally, a detailed analysis of the impact of defect density (Nt), interface defects (ETL/Perv, Perv/HTL), temperature, and work function on the functionality of 18 different CsSnGeI3-based PSCs is conducted. The simulation findings demonstrate that SnO2/CsSnGeI3/CNTS is the most efficient optimized PSC among all of the simulated structures, with a PCE of 27.33%, Jsc of 28.04 mA/cm2, FF of 85%, and Voc of 1.14 V.

Alothman A, Mohammad S. Hydrothermal Synthesis, Phase Analysis, and Magneto-Electronic Characterizations of Lead-Free Ferroelectric BM2+(Zn, Ca, Mg)T-BFO System

In this study, lead-free BiM2+(Zn, Ca, Mg)Ti-BiFeO3 ceramics are fabricated under eco-friendly hydrothermal reaction conditions at 250 °C. XRD patterns show that all the synthesized compounds exhibit a phase coexistence of monoclinic and tetragonal perovskite-type structures with a morphotropic phase boundary at x = 0.4, with minimum impurity. The calculated average crystallite/grain size of the samples was close to 50 nm at full width at half-maximum of the main peak. The corresponding bonds of the constituent elements were observed by FTIR analysis, which further supports the formation of the local structure. EDS analyses detect all of the elements, their quantities, and compositional homogeneity. SEM data show agglomerated and nearly spherical morphology with an average particle size of about 128 nm. All synthesized ceramic powders revealed thermal stability with trivial mass loss up to investigated high temperatures (1000 οC). The dielectric constant reached its maximum at 38.7 MHz and finally remained constant after 80 MHz for all nanoceramics. Because of the complementary impact of different compositions, the most effective piezoelectric characteristics of d33 = 136 pCN-1, Pr = 8.6 pCN-1 cm-2, and kp = 11% at 30 °C were attained at x = 0.4 content for 0.4BiCaTi-0.6BiFeO3 ceramic. The measured magnetic hysteresis data (M-H curve) showed a weak ferromagnetic nature with the highest moment of ∼0.23 emu/g for 0.4BiCaTi-0.6BiFeO3, and other samples exhibited negligible ferromagnetic to diamagnetic transition. The optical response study shows that the 0.4BiMgTi-0.6BiFeO3 sample yielded the maximal transmittance (50%), whereas the 0.4BiCaTi-0.6BiFeO3 compound exhibited the highest refractive index. The calculated large band gap shows a high insulating or dielectric nature. Our findings demonstrate that the BiM2+Ti-BiFeO3 system, which was fabricated using a low-temperature hydrothermal technique, is an excellent lead-free piezoelectric and multiferroic nanoceramic.

Experimental and computational DFT, drift-diffusion studies of cobalt-based hybrid perovskite crystals as absorbers in perovskite solar cells

The optimised designs of dimethyl ammonium cobalt formate-based perovskite crystals [(CH3)2NH2]Co(HCOO)3 were experimentally synthesized and computationally utilized as absorbers for perovskite solar cells (PSCs). Crystals were grown using solvothermal synthesis. Additive materials (Fe, Ni) are responsible for the growth and suppression of crystals in the micrometre range. Temperature and pressure were altered to obtain optimum growth conditions. Grown crystals were characterized by spectroscopy (XRD, FT-IR, UV-Vis) and optical microscopy. Combined density functional theory (DFT) and drift-diffusion modelling frameworks were simulated. These simulators were used to examine various perovskite absorbers for solar-cell configurations. Field calculations were used to examine the structural stability, band structure, and electronic contribution of the constituent elements in [(CH3)2NH2]Co1-nMn(HCOO)3 (M = Fe, Ni and n = 0, 0.1) as absorber material. Conventional TiO2 and spiro-OMeTAD were used as the electron-transport layer and hole-transport layer, respectively, and Pt was used as a back contact. Comprehensive analysis of the effects of several parameters (layer thickness, series and shunt resistances, temperature, generation-recombination rates, current-voltage density, quantum efficiency) was carried out using simulation. Our proposed strategy may pave the way for further design of new absorber materials for PSCs.

Emerging BaZrS3 and Ba(Zr,Ti)S3 Chalcogenide Perovskite Solar Cells: A Numerical Approach Toward Device Engineering and Unlocking Efficiency

BaZrS3 chalcogenide perovskites have emerged as a promising absorber due to their exceptional properties. However, there are no experimental reports on the applicability of BaZrS3 in photovoltaics. Thus, theoretical knowledge of device structure engineering is essential for its successful fabrication. In this regard, we have proposed various BaZrS3 device configurations by altering 12 electron transport layers (ETLs) in combination with 13 hole transport layers (HTLs) using SCAPS-1D, wherein a total of 782 devices are simulated by tuning the thickness, carrier concentration, and defect density of BaZrS3, ETLs, and HTLs. Interestingly, the absorber's thickness optimization enhanced the absorption in the device by 2.31 times, elevating the generation rate of charge carriers, while the increase in its carrier concentration boosted the built-in potential from 0.8 to 1.68 V, reducing the accumulation of charge carriers at the interfaces. Notably, on further optimization of ETL and HTL combinations, the best power conversion efficiency (PCE) of 28.08% is achieved for FTO/ZrS2/BaZrS3/SnS/Au, occurring due to the suppressed barrier height of 0.1 eV at the ZrS2/BaZrS3 interface and degenerate behavior of SnS, which increased charge carrier transportation and conductivity of the devices. Upon optimizing the work function, an ohmic contact is achieved for Pt, boosting the PCE to 28.17%. Finally, the impact of Ti alloying on BaZrS3 properties is examined on the champion FTO/ZrS2/BaZrS3/SnS/Pt device where the maximum PCE of 32.58% is obtained for Ba(Zr0.96,Ti0.04)S3 at a thickness of 700 nm due to extended absorption in the NIR region. Thus, this work opens doors to researchers for the experimental realization of high PCE in BaZrS3 devices.

Improving the efficiency of a CIGS solar cell to above 31% with Sb2S3 as a new BSF: a numerical simulation approach by SCAPS-1D

The remarkable performance of copper indium gallium selenide (CIGS)-based double heterojunction (DH) photovoltaic cells is presented in this work. To increase all photovoltaic performance parameters, in this investigation, a novel solar cell structure (FTO/SnS2/CIGS/Sb2S3/Ni) is explored by utilizing the SCAPS-1D simulation software. Thicknesses of the buffer, absorber and back surface field (BSF) layers, acceptor density, defect density, capacitance-voltage (C-V), interface defect density, rates of generation and recombination, operating temperature, current density, and quantum efficiency have been investigated for the proposed solar devices with and without BSF. The presence of the BSF layer significantly influences the device's performance parameters including short-circuit current (Jsc), open-circuit voltage (Voc), fill factor (FF), and power conversion efficiency (PCE). After optimization, the simulation results of a conventional CIGS cell (FTO/SnS2/CIGS/Ni) have shown a PCE of 22.14% with Voc of 0.91 V, Jsc of 28.21 mA cm-2, and FF of 86.31. Conversely, the PCE is improved to 31.15% with Voc of 1.08 V, Jsc of 33.75 mA cm-2, and FF of 88.50 by introducing the Sb2S3 BSF in the structure of FTO/SnS2/CIGS/Sb2S3/Ni. These findings of the proposed CIGS-based double heterojunction (DH) solar cells offer an innovative method for realization of high-efficiency solar cells that are more promising than the previously reported traditional designs.

Proton Irradiation on Halide Perovskites: Numerical Calculations

The results of numerical SRIM and SCAPS calculations for the ionization, displacement and heating of hybrid perovskites under the influence of protons (E = 0.15, 3.0 and 18 MeV) are presented and show that the lowest transfer energy is demonstrated by the MAPbI3, FAPbBr3 and FAPbI3 compounds, which represent the greatest potential for use as solar cells in space devices. On the other hand, it is found that perovskite compositions containing FA and Cs and with mixed cations are the most stable from the point of view of the formation of vacancies and phonons and are also promising as radiation-resistant materials with respect to powerful proton fluxes. Taking into account the lateral distribution of proton tracks showed that, at an energy level of several MeV, the release of their energy can be considered uniform over the depth and area of the entire solar cell, suggesting that the simple protection by plastic films from the low-energy protons is sufficient.

Pivotal avenue for hybrid electron transport layer-based perovskite solar cells with improved efficiency

This study conducted a simulative analysis of different hybrid perovskite solar cells with various hybrid electron transport layers (ETL) and hole transport layers (HTL). The electron transport layer boosts durability, lowers production costs, increases stability, improves light absorption, and increases efficiency. Hybrid ETLs are taken into consideration to improve the device's performance. The selected hybrid ETLs (PCBM-SnS2, TiO2-SnO2, and PCBM-PCPB) were modeled with four hybrid perovskite absorbers (CsPbI3, FAPbI3, MAPbI3, and FAMAPbI3) and five HTLs (PEDOT: PSS, CuI, Spiro-OMeTAD, CBTS, and NiO). Three sets of solar cells are found to be the most effective configurations after investigating over sixty different combinations of perovskite solar cell architectures. The structures show CBTS as the efficient HTL for FAMAPbI3 with all three hybrid ETLs. Besides, a holistic analysis of the effect of several factors such as the defect density and thickness of the absorber layer, temperature, parasitic resistances, capacitance, Mott-Schottky, impedance, conduction band offset, and current density-voltage and quantum efficiency characteristics is performed. The results show a maximum power conversion efficiency of 25.57%, 26.35%, and 23.36% with PCBM-SnS2, TiO2-SnO2, and PCBM-PCPB respectively. Among the studied hybrid ETLs, perovskite solar cell associated with TiO2-SnO2 has depicted a superior performance (Voc = 1.12 V, Jsc = 26.88 mA/cm2, FF = 87.27%). The efficiency of the perovskite solar cell using this study has been drastically enhanced compared to the previous experimental report. The proposed strategy provides a new avenue for attaining clean energy and allows researchers to pave the way for further design optimization to obtain high-performance solar cell devices.

Lead-free novel perovskite Ba3AsI3: First-principles insights into its electrical, optical, and mechanical properties

Lead-free halide perovskites are a crucial family of materials in the fabrication of solar cells. At present, Solar cells are facing several challenges such as mechanical and thermodynamic instability, toxicity, unsuitable optical parameters, bandgap, and absorption coefficient. Ba3AsI3 is a halide perovskite which has demonstrated good efficiency and tremendous promise for usage in solar cell applications, and it offers a possible solution to these issues. In this study, the properties of the Ba3AsI3 perovskite solar cell were investigated using first-principles density functional theory (FP-DFT) calculations with the CASTEP (Cambridge serial total energy package) formulation. Most of its physical qualities, including its elasticity, electrical composition, bonding, optoelectronic characteristics, and optical characteristics have not yet been explored. In this work, these unexplored properties have been thoroughly investigated using density functional theory-based computations. The Born-Huang criterion and phonon dispersion characteristics have revealed that the material is mechanically stable. The bonding nature has been investigated using the density of states curves, Mulliken population analysis, and electronic charge density. Additionally, different elastic parameters demonstrate that Ba3AsI3 has reasonably high machinability and is mechanically isotropic. ELATE's three-dimensional visualization and optical properties also show isotropic behavior in all directions. The band structure shows that the bandgap is direct. Based on its direct bandgap, stability, large range of absorption coefficient, and suitable optical parameters, Ba3AsI3 is recommended as an absorber layer for solar cell fabrication in a near future.

Optimization and Performance Analysis of a TiO2/i-CH3NH3SnBr3/CsPbI3/Al(BSF) Heterojunction Perovskite Solar Cell for Enhanced Efficiency

This paper reports the simulation and optimization of heterojunction perovskite solar cells (PSCs) with a proposed structure of TiO2/i-CH3NH3SnBr3/CsPbI3/Al(BSF) using SCAPS-1D software. The purpose of this study is to investigate the performance of the PSC with CsPbI3 perovskite active layers and i-CH3NH3SnBr3 as the permeable layer. Therefore, the thicknesses of the layers of the heterojunction perovskite are modified in order to find a better conversion efficiency of the solar cell, where the latter's performance is improved by optimizing the absorber's thickness, which is found to be 1 μm, with a permeable layer of 15 μm. The device efficiency of the i-CH3NH3SnBr3/CsPbI3 heterojunction is improved to 38.98%, and optimized parameters are Voc = 1.21 mV, Jsc = 35.63 mA/cm2, and FF = 89.84%. The acceptor concentration (Na), donor concentration (Nd), defect density, and series and shunt resistances are also investigated.

Achieving above 24% efficiency with non-toxic CsSnI3 perovskite solar cells by harnessing the potential of the absorber and charge transport layers

Lead toxicity is a barrier to the widespread commercial manufacture of lead halide perovskites and their use in solar photovoltaic (PV) devices. Eco-friendly lead-free perovskite solar cells (PSCs) have been developed using certain unique non- or low-toxic perovskite materials. In this context, Sn-based perovskites have been identified as promising substitutes for Pb-based perovskites due to their similar characteristics. However, Sn-based perovskites suffer from chemical instability, which affects their performance in PSCs. This study employs theoretical simulations to identify ways to improve the efficiency of Sn-based PSCs. The simulations were conducted using the SCAPS-1D software, and a lead-free, non-toxic, and inorganic perovskite absorber layer (PAL), i.e. CsSnI3 was used in the PSC design. The properties of the hole transport layer (HTL) and electron transport layer (ETL) were tuned to optimize the performance of the device. Apart from this, seven different combinations of HTLs were studied, and the best-performing combination was found to be ITO/PCBM/CsSnI3/CFTS/Se, which achieved a power conversion efficiency (PCE) of 24.73%, an open-circuit voltage (VOC) of 0.872 V, a short-circuit current density (JSC) of 33.99 mA cm-2 and a fill factor (FF) of 83.46%. The second highest PCE of 18.41% was achieved by the ITO/PCBM/CsSnI3/CuSCN/Se structure. In addition to optimizing the structure of the PSC, this study also analyzes the current density-voltage (J-V) along with quantum efficiency (QE), as well as the impact of series resistance, shunt resistance, and working temperature, on PV performance. The results demonstrate the potential of the optimized structure identified in this study to enhance the standard PCE of PSCs. Overall, this study provides important insights into the development of lead-free absorber materials and highlights the potential of using CsSnI3 as the PAL in PSCs. The optimized structure identified in this study can be used as a base for further research to improve the efficiency of Sn-based PSCs.

Inorganic novel cubic halide perovskite Sr3AsI3: Strain-activated electronic and optical properties

In recent years, inorganic perovskite materials have attracted a lot of attention in the field of solar technology due to their exceptional structural, optical, and electronic properties. This study thoroughly investigated, using first-principles density-functional theory (FP-DFT), the impact of compressive and tensile strain on the structural, optical, and electrical properties of the inorganic cubic perovskite Sr3AsI3. The unstrained planar Sr3AsI3 molecule exhibits a direct bandgap of 1.265 eV value at Γ point. The bandgap of the Sr3AsI3 perovskite is lowered to 1.212 eV when the relativistic spin-orbital coupling (SOC) effect is subjected in the observations. In addition, the structure's bandgap exhibits a falling prevalence due to compressive strain and a slight rise due to tensile strain. The optical indicators such as dielectric functions, absorption coefficient, reflectivity, and electron loss function show that this component has a great ability to absorb in the visible range in accordance with band characteristics. When compressive strain is raised, it is discovered that the spikes of the dielectric constant of Sr3AsI3 move to lower photon energy (redshift), and conversely, while growing tensile strain, it exhibits increased photon energy changing behavior (blueshift). As a result, the Sr3AsI3 perovskite is regarded as being ideal for use in solar cells for the production of electricity and light management.

Harnessing the potential of CsPbBr3-based perovskite solar cells using efficient charge transport materials and global optimization

Perovskite solar cells (PSCs) have become a possible alternative to traditional photovoltaic devices for their high performance, low cost, and ease of fabrication. Here in this study, the SCAPS-1D simulator numerically simulates and optimizes CsPbBr₃-based PSCs under the optimum illumination situation. We explore the impact of different back metal contacts (BMCs), including Cu, Ag, Fe, C, Au, W, Pt, Se, Ni, and Pd combined with the TiO₂ electron transport layer (ETL) and CFTS hole transport layer (HTL), on the performance of the devices. After optimization, the ITO/TiO₂/CsPbBr₃/CFTS/Ni structure showed a maximum power conversion efficiency (PCE or η) of 13.86%, with Ni as a more cost-effective alternative to Au. After the optimization of the BMC the rest of the investigation is conducted both with and without HTL mode. We investigate the impact of changing the thickness and the comparison with acceptor and defect densities (with and without HTL) of the CsPbBr₃ perovskite absorber layer on the PSC performance. Finally, we optimized the thickness, charge carrier densities, and defect densities of the absorber, ETL, and HTL, along with the interfacial defect densities at HTL/absorber and absorber/ETL interfaces to improve the PCE of the device; and the effect of variation of these parameters is also investigated both with and without HTL connected. The final optimized configuration achieved a V_OC of 0.87 V, J_SC of 27.57 mA cm^-2, FF of 85.93%, and PCE of 20.73%. To further investigate the performance of the optimized device, we explore the impact of the temperature, shunt resistance, series resistance, capacitance, generation rate, recombination rate, Mott-Schottky, JV, and QE features of both with and without HTL connected. The optimized device offers the best thermal stability at a temperature of 300 K. Our study highlights the potential of CsPbBr₃-based PSCs and provides valuable insights for their optimization and future development.

Deep Insights into the Coupled Optoelectronic and Photovoltaic Analysis of Lead-Free CsSnI3 Perovskite-Based Solar Cell Using DFT Calculations and SCAPS-1D Simulations

CsSnI₃ is considered to be a viable alternative to lead (Pb)-based perovskite solar cells (PSCs) due to its suitable optoelectronic properties. The photovoltaic (PV) potential of CsSnI₃ has not yet been fully explored due to its inherent difficulties in realizing defect-free device construction owing to the nonoptimized alignment of the electron transport layer (ETL), hole transport layer (HTL), efficient device architecture, and stability issues. In this work, initially, the structural, optical, and electronic properties of the CsSnI₃ perovskite absorber layer were evaluated using the CASTEP program within the framework of the density functional theory (DFT) approach. The band structure analysis revealed that CsSnI₃ is a direct band gap semiconductor with a band gap of 0.95 eV, whose band edges are dominated by Sn 5s/5p electrons After performing the DFT analysis, we investigated the PV performance of a variety of CsSnI₃-based solar cell configurations utilizing a one-dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs such as IGZO, WS₂, CeO₂, TiO₂, ZnO, PCBM, and C₆₀. Simulation results revealed that the device architecture comprising ITO/ETL/CsSnI₃/CuI/Au exhibited better photoconversion efficiency among more than 70 different configurations. The effect of the variation in the absorber, ETL, and HTL thickness on PV performance was analyzed for the above-mentioned configuration thoroughly. Additionally, the impact of series and shunt resistance, operating temperature, capacitance, Mott-Schottky, generation, and recombination rate on the six superior configurations were evaluated. The J-V characteristics and the quantum efficiency plots for these devices are systematically investigated for in-depth analysis. Consequently, this extensive simulation with validation results established the true potential of CsSnI₃ absorber with suitable ETLs including ZnO, IGZO, WS₂, PCBM, CeO₂, and C₆₀ ETLs and CuI as HTL, paving a constructive research path for the photovoltaic industry to fabricate cost-effective, high-efficiency, and nontoxic CsSnI₃ PSCs.

Selection of a compatible electron transport layer and hole transport layer for the mixed perovskite FA0.85Cs0.15Pb (I0.85Br0.15)3, towards achieving novel structure and high-efficiency perovskite solar cells: a detailed numerical study by SCAPS-1D

The first and foremost intent of our present study is to design a perovskite solar cell favorable for realistic applications with excellent efficiency by utilizing SCAPS-1D. To ensure this motive, the detection of a compatible electron transport layer (ETL) and hole transport layer (HTL) for the suggested mixed perovskite layer entitled FA_0.85Cs_0.15Pb (I_0.85Br_0.15)₃ (MPL) was carried out, employing diver ETLs such as SnO_2, PCBM, TiO₂, ZnO, CdS, WO₃ and WS₂, and HTLs such as Spiro-OMeTAD, P3HT, CuO, Cu₂O, CuI, and MoO_3. The attained simulated results, especially for FTO/SnO₂/FA_0.85Cs_0.15Pb (I_0.85Br_0.15)₃/Spiro-OMeTAD/Au, have been authenticated by the theoretical and experimental data, which endorse our simulation process. From the detailed numerical analysis, WS₂ and MoO₃ were chosen as ETL and HTL, respectively, for designing the proposed novel structure of FA_0.85Cs_0.15Pb (I_0.85Br_0.15)₃-based perovskite solar cells. With the inspection of several parameters such as variation of the thickness of FA_0.85Cs_0.15Pb (I_0.85Br_0.15)₃, WS_2, and MoO₃ including different defect densities, the novel proposed structure has been optimized, and a noteworthy efficiency of 23.39% was achieved with the photovoltaic parameters of V_OC = 1.07 V, J_SC = 21.83 mA cm^-2, and FF = 73.41%. The dark J-V analysis unraveled the reasons for the excellent photovoltaic parameters of our optimized structure. Furthermore, the scrutinizing of QE, C-V, Mott-Schottky plot, and the impact of the hysteresis of the optimized structure was executed for further investigation. Our overall investigation disclosed the fact that the proposed novel structure (FTO/WS₂/FA_0.85Cs_0.15Pb (I_0.85Br_0.15)₃/MoO₃/Au) can be attested as a supreme structure for perovskite solar cells with greater efficiency as well as admissible for practical purposes.

Investigation of Polymer/Si Thin Film Tandem Solar Cell Using TCAD Numerical Simulation

The current study introduces a two-terminal (2T) thin-film tandem solar cell (TSC) comprised of a polymer-based top sub cell and a thin crystalline silicon (c-Si) bottom sub cell. The photoactive layer of the top sub cell is a blend of PDTBTBz-2F as a polymer donor and PC₇₁BM as a fullerene acceptor. Initially, a calibration of the two sub cells is carried out against experimental studies, providing a power conversion efficiency (PCE) of 9.88% for the top sub cell and 14.26% for the bottom sub cell. Upon incorporating both sub cells in a polymer/Si TSC, the resulting cell shows a PCE of 20.45% and a short circuit current density (J_sc) of 13.40 mA/cm². Then, we optimize the tandem performance by controlling the valence band offset (VBO) of the polymer top cell. Furthermore, we investigate the impact of varying the top absorber defect density and the thicknesses of both absorber layers in an attempt to obtain the maximum obtainable PCE. After optimizing the tandem cell and at the designed current matching condition, the J_sc and PCE of the tandem cell are improved to 16.43 mA/cm² and 28.41%, respectively. Based on this TCAD simulation study, a tandem configuration established from an all thin-film model may be feasible for wearable electronics applications. All simulations utilize the Silvaco Atlas package where the cells are subjected to standard one Sun (AM1.5G, 1000 W/m²) spectrum illumination.

Proposal and Design of Flexible All-Polymer/CIGS Tandem Solar Cell

Tandem solar cells (TSCs) have attracted prodigious attention for their high efficiency, which can surmount the Shockley-Queisser limit for single-junction solar cells. Flexible TSCs are lightweight and cost-effective, and are considered a promising approach for a wide range of applications. In this paper, a numerical model, based on TCAD simulation, is presented to assess the performance of a novel two-terminal (2T) all-polymer/CIGS TSC. To confirm the model, the obtained simulation results were compared with standalone fabricated all-polymer and CIGS single solar cells. Common properties of the polymer and CIGS complementary candidates are their non-toxicity and flexibility. The initial top all-polymer solar cell had a photoactive blend layer (PM7:PIDT), the optical bandgap of which was 1.76 eV, and the initial bottom cell had a photoactive CIGS layer, with a bandgap of 1.15 eV. The simulation was then carried out on the initially connected cells, revealing a power conversion efficiency (PCE) of 16.77%. Next, some optimization techniques were applied to enhance the tandem performance. Upon treating the band alignment, the PCE became 18.57%, while the optimization of polymer and CIGS thicknesses showed the best performance, reflected by a PCE of 22.73%. Moreover, it was found that the condition of current matching did not necessarily meet the maximum PCE condition, signifying the essential role of full optoelectronic simulations. All TCAD simulations were performed via an Atlas device simulator, where the light illumination was AM1.5G. The current study can offer design strategies and effective suggestions for flexible thin-film TSCs for potential applications in wearable electronics.

An extensive study on multiple ETL and HTL layers to design and simulation of high-performance lead-free CsSnCl3-based perovskite solar cells

Cesium tin chloride (CsSnCl₃) is a potential and competitive absorber material for lead-free perovskite solar cells (PSCs). The full potential of CsSnCl₃ not yet been realized owing to the possible challenges of defect-free device fabrication, non-optimized alignment of the electron transport layer (ETL), hole transport layer (HTL), and the favorable device configuration. In this work, we proposed several CsSnCl₃-based solar cell (SC) configurations using one dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs like indium-gallium-zinc-oxide (IGZO), tin-dioxide (SnO₂), tungsten disulfide (WS₂), ceric dioxide (CeO₂), titanium dioxide (TiO₂), zinc oxide (ZnO), C₆₀, PCBM, and HTLs of cuprous oxide (Cu₂O), cupric oxide (CuO), nickel oxide (NiO), vanadium oxide (V₂O₅), copper iodide (CuI), CuSCN, CuSbS₂, Spiro MeOTAD, CBTS, CFTS, P3HT, PEDOT:PSS. Simulation results revealed that ZnO, TiO₂, IGZO, WS₂, PCBM, and C₆₀ ETLs-based halide perovskites with ITO/ETLs/CsSnCl₃/CBTS/Au heterostructure exhibited outstanding photoconversion efficiency retaining nearest photovoltaic parameters values among 96 different configurations. Further, for the six best-performing configurations, the effect of the CsSnCl₃ absorber and ETL thickness, series and shunt resistance, working temperature, impact of capacitance, Mott-Schottky, generation and recombination rate, current-voltage properties, and quantum efficiency on performance were assessed. We found that ETLs like TiO₂, ZnO, and IGZO, with CBTS HTL can act as outstanding materials for the fabrication of CsSnCl₃-based high efficiency (η ≥ 22%) heterojunction SCs with ITO/ETL/CsSnCl₃/CBTS/Au structure. The simulation results obtained by the SCAPS-1D for the best six CsSnCl₃-perovskites SC configurations were compared by the wxAMPS (widget provided analysis of microelectronic and photonic structures) tool for further validation. Furthermore, the structural, optical and electronic properties along with electron charge density, and Fermi surface of the CsSnCl₃ perovskite absorber layer were computed and analyzed using first-principle calculations based on density functional theory. Thus, this in-depth simulation paves a constructive research avenue to fabricate cost-effective, high-efficiency, and lead-free CsSnCl₃ perovskite-based high-performance SCs for a lead-free green and pollution-free environment.

Optical performance analysis of InP nanostructures for photovoltaic applications

In this article, we have performed a comparative analysis of six different types of nanostructures that can improve photon management for photovoltaic applications. These nanostructures act as anti-reflective structures by improving the absorption characteristics and tailoring the optoelectronic properties of the associated devices. The absorption enhancement in indium phosphide (InP) and silicon (Si) based cylindrical nanowires (CNWs) and rectangular nanowires (RNWs), truncated nanocones (TNCs), truncated nanopyramids (TNPs), inverted truncated nanocones (ITNCs), and inverted truncated nanopyramids (ITNPs) are computed using the finite element method (FEM) based commercial COMSOL Multiphysics package. The influence of geometrical dimensions of the investigated nanostructures such as period (P), diameter (D), width (W), filling ratio (FR), bottom W and D (W_bot/D_bot), and top W and D (W_top/D_top) on the optical performance are analyzed in detail. Optical short circuit current density (J_sc) is computed using the absorption spectra. The results of numerical simulations indicate that InP nanostructures are optically superior to Si nanostructures. In addition to this, the InP TNP generates an optical short circuit current density (J_sc) of 34.28 mA cm⁻², which is ∼10 mA cm⁻² higher than its Si counterpart. The effect of incident angle on the ultimate efficiency of the investigated nanostructures in transverse electric (TE) and transverse magnetic (TM) modes is also explored. Theoretical insights into the design strategies of different nanostructures proposed in this article will act as a benchmark for choosing the device dimensions of appropriate nanostructures for the fabrication of efficient photovoltaic devices.

The optical performance of different indium phosphide (InP) nanostructures are investigated using Wave Optics Module of COMSOL Multiphysics. Our results indicate that InP based nanostructures outperform silicon based nanostructures.

Combined DFT, SCAPS-1D, and wxAMPS frameworks for design optimization of efficient Cs2BiAgI6-based perovskite solar cells with different charge transport layers

In this study, combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 double perovskite-based solar cells. First-principles calculations are employed to investigate the structural stability, optical responses, and electronic contribution of the constituent elements in Cs2BiAgI6 absorber material, where SCAPS-1D and wxAMPS simulators are used to scrutinize different configurations of Cs2BiAgI6 solar cells. Here, PCBM, ZnO, TiO2, C60, IGZO, SnO2, WS2, and CeO2 are used as ETL, and Cu2O, CuSCN, CuSbS2, NiO, P3HT, PEDOT:PSS, spiro-MeOTAD, CuI, CuO, V2O5, CBTS, CFTS are used as HTL, and Au is used as a back contact. About ninety-six combinations of Cs2BiAgI6-based solar cell structures are investigated, in which eight sets of solar cell structures are identified as the most efficient structures. Besides, holistic investigation on the effect of different factors such as the thickness of different layers, series and shunt resistances, temperature, capacitance, Mott-Schottky and generation-recombination rates, and J-V (current-voltage density) and QE (quantum efficiency) characteristics is performed. The results show CBTS as the best HTL for Cs2BiAgI6 with all eight ETLs used in this work, resulting in a power conversion efficiency (PCE) of 19.99%, 21.55%, 21.59%, 17.47%, 20.42%, 21.52%, 14.44%, 21.43% with PCBM, TiO2, ZnO, C60, IGZO, SnO2, CeO2, WS2, respectively. The proposed strategy may pave the way for further design optimization of lead-free double perovskite solar cells.