Thickness Of Electron Transport Layer Research Articles

Enhancing Efficiency and Stability of Inverted Perovskite Solar Cells through Solution-Processed and Structurally Ordered Fullerene.

The electron transporting layer (ETL) used in high performance inverted perovskite solar cells (PSCs) is typically composed of C60, which requires time-consuming and costly thermal evaporation deposition, posing a significant challenge for large-scale production. To address this challenge, herein, we present a novel design of solution-processible electron transporting material (ETM) by grafting a non-fullerene acceptor fragment onto C60. The synthesized BTPC60 exhibits an exceptional solution processability and well-organized molecular stacking pattern, enabling the formation of uniform and structurally ordered film with high electron mobility. When applied as ETL in inverted PSCs, BTPC60 not only exhibits excellent interfacial contact with the perovskite layer, resulting in enhanced electron extraction and transfer efficiency, but also effectively passivates the interfacial defects to suppress non-radiative recombination. Resultant BTPC60-based inverted PSCs deliver an impressive power conversion efficiency (PCE) of 25.3% and retain almost 90% of the initial values after aging at 85°C for 1500 hours in N2. More encouragingly, the solution-processed BTPC60 ETL demonstrates remarkable film thickness tolerance, and enables a high PCE up to 24.8% with the ETL thickness of 200 nm. Our results highlight BTPC60 as a promising solution-processed fullerene-based ETM, opening an avenue for improving the scalability of efficient and stable inverted PSCs.

Investigating novel perovskites of lead-free flexible solar cell CH3NH3BiI3 and their photovoltaic performance with efficiency over 26%

Perovskite solar cells are increasing attention due to their unique characteristics in the field of photovoltaic technology. Lead-based perovskite solar cells are particularly notable for their high efficiency. However, their commercial production is limited because of the use of lead-based absorbers. As a result, research has shifted towards exploring lead-free alternatives in the realm of perovskite materials. This study utilizes SCAPS-1D simulation software to optimize the performance of a lead-free flexible solar cell. Lead (Pb), a group 14 element, is proposed to be replaced by bismuth (Bi), a group 15 element. We investigate how the selection of configurations for the Electron Transport Layer (ETL), Hole Transport Layer (HTL), and absorber layer impacts solar cell performance. This study represents a comprehensive examination of this material. The device optimization involves using a fluorine-doped tin oxide (FTO) substrate, cadmium sulfide (CdS), tungsten disulfide (WS2), titanium dioxide (TiO2), and fullerene (C60) as ETL components, methyl ammonium bismuth iodide (CH3NH3BiI3) as the absorber, molybdenum disulfide (MoS2) as the HTL, and platinum (Pt) as the electrode. In addition to optimizing ETL and HTL configurations, this study explores the effects of various factors such as absorber, ETL, and HTL thickness, shunt and series resistance, temperature variations, Mott-Schottky behavior, capacitance, recombination, generation rates, J-V characteristics, and quantum energy. The results show that the solar cell configuration using FTO/CdS/CH3NH3BiI3/MoS2/Pt achieves an efficiency of 26.60 %, a current density (JSC) of 32.02 mA/cm2, an open circuit voltage (VOC) of 0.974 V, and a fill factor (FF) of 85.24 %. This represents a significant improvement compared to previous research. This detailed simulation analysis enables researchers to develop cost-effective and highly efficient perovskite solar cells (PSCs), driving advancements in solar technology.

Exploring Multi‐Level ETL and HTL Configurations for High‐Efficiency Lead‐Free Cs2AgBiBr6 Double Perovskite Solar Cells: A Design and Simulation Study

Cs2AgBiBr6 is a promising lead‐free double perovskite solar cells (PSCs) material. Its full potential has yet to be realized due to issues with its large band gap and the optimization of the alignment of the electron transport layer (ETL) and hole transport layer (HTL). The photovoltaic performance of Cs2AgBiBr6‐based devices has been optimized using ZnO, IGZO, TiO2, WS2, PCBM, and C60 ETLs and Cu2O, CuScN, CuSbS2, NiO, P3HT, PEDOT: PSS, Spiro MeOTAD, CuI, CuO, V2O5, CBTS, and CFTS HTLs. It has been observed by simulation study that Cs2AgBiBr6‐based devices exhibit remarkably high photoconversion efficiency when combined with certain ETLs. To better understand the performance, we examine how the best device structures are affected by the absorber and ETL thickness, ETL carrier density, series and shunt resistance, generation, and recombination rate. The findings suggest that TiO2 and ZnO ETLs, in conjunction with CBTS HTL, exhibit good potential for producing high‐efficiency (η > 13%) Cs2AgBiBr6‐based heterojunction solar cells with an ITO/ETL/Cs2AgBiBr6/CBTS/Au device structure. Optimization of the valence band offset (VBO) at the CBTS/Cs2AgBiBr6 interface reveals that reduced VBO value has a beneficial impact on the performance of the solar cell. This modeling work gives a prospective route for manufacturing lead‐free Cs2AgBiBr6 PSCs.

Advanced Optoelectronic Modeling and Optimization of HTL-Free FASnI3/C60 Perovskite Solar Cell Architecture for Superior Performance.

In this study, a novel perovskite solar cell (PSC) architecture is presented that utilizes an HTL-free configuration with formamide tin iodide (FASnI3) as the active layer and fullerene (C60) as the electron transport layer (ETL), which represents a pioneering approach within the field. The elimination of hole transport layers (HTLs) reduces complexity and cost in PSC heterojunction structures, resulting in a simplified and more cost-effective PSC structure. In this context, an HTL-free tin HC(NH2)2SnI3-based PSC was simulated using the solar cell capacitance simulator (SCAPS) within a one-dimensional framework. Through this approach, the device performance of this novel HTL-free FASnI3-based PSC structure was engineered and evaluated. Key performance parameters, including the open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), power conversion efficiency (PCE), I-V characteristics, and quantum efficiency (QE), were systematically assessed through the modulation of physical parameters across various layers of the device. A preliminary analysis indicated that the HTL-free configuration exhibited improved I-V characteristics, with a PCE increase of 1.93% over the HTL configuration due to improved electron and hole extraction characteristics, reduced current leakage at the back contact, and reduced trap-induced interfacial recombination. An additional boost to the device's key performance parameters has been achieved through the further optimization of several physical parameters, such as active layer thickness, bulk and interface defects, ETL thickness, carrier concentration, and back-contact materials. For instance, increasing the thickness of the active layer PSC up to 1500 nm revealed enhanced PV performance parameters; however, further increases in thickness have resulted in performance saturation due to an increased rate of hole-electron recombination. Moreover, a comprehensive correlation study has been conducted to determine the optimum thickness and donor doping level for the C60-ETL layer in the range of 10-200 nm and 1012-1019 cm-3, respectively. Optimum device performance was observed at an ETL-C60 ultra-thin thickness of 10 nm and a carrier concentration of 1019 cm-3. To maintain improved PCEs, bulk and interface defects must be less than 1016 cm-3 and 1015 cm-3, respectively. Additional device performance improvement was achieved with a back-contact work function of 5 eV. The optimized HTL-free FASnI3 structure demonstrated exceptional photovoltaic performance with a PCE of 19.63%, Voc of 0.87 V, Jsc of 27.86 mA/cm2, and FF of 81%. These findings highlight the potential for highly efficient photovoltaic (PV) technology solutions based on lead-free perovskite solar cell (PSC) structures that contribute to environmental remediation and cost-effectiveness.

Red and green inverted top-emitting quantum dot light-emitting diodes using CMOS-based electrodes for microdisplay applications

Silicon (Si) substrates and complementary metal-oxide-semiconductor (CMOS) technology are being used in microdisplays in augmented reality/virtual reality devices owing to higher pixel resolution. Quantum-dot light-emitting diodes (QLEDs) incorporating colloidal quantum dots have emerged as promising devices for display applications owing to their exceptional color, high luminance, and solution processibility. However, studies on QLEDs on Si, particularly for microdisplay applications, remain limited. This study investigated the device characteristics of inverted top-emitting QLEDs using Si substrates and various CMOS process-based electrode materials (aluminum (Al), Al/titanium nitride (TiN), titanium, cobalt, and tungsten) for microdisplay applications. Devices incorporating a thin TiN layer on an Al electrode exhibited the highest efficiency and luminance compared to those with other electrodes. We successfully fabricated red and green inverted top-emitting QLEDs using microdisplay pixel-structured Al/TiN electrodes, with pixel pitch and fill factor of 10.8 μm × 3.6 μm and 72.5 %, respectively. Further, the device efficiency was optimized by changing hole and electron transport layer thicknesses, resulting in different efficiencies and electroluminescence spectra owing to the microcavity effect. Optical simulations demonstrated consistency with the measured values. Thus, the selection of the bottom electrode and a suitable design that considers the microcavity effect are crucial for high-performance QLED-based microdisplays.

Enhanced Conversion Efficiency in MAPbI3 Perovskite Solar Cells through Parameters Optimization via SCAPS-1D Simulation

In this study, various factors affecting the efficiency of the MAPbI3 perovskite solar cell (PSC) were analyzed using the SCAPS-1D simulation program. The basic device analyzed in this study had a structure of ITO/TiO2/MAPbI3/Cu2O/Au. The thickness of each layer (electron transport layer (ETL), perovskite absorption layer (PAL), and hole transport layer (HTL)), PAL defect density and interface defect density were investigated as parameters. The optimized parameters that yielded the highest light conversion efficiency were an ETL (TiO2) thickness of 100 nm, a PAL (MAPbI3) thickness of 1300 nm, an HTL (Cu2O) thickness of 400 nm, a PAL defect density of 1014 cm−3, and an interface defect density of 1013 cm−3 for both absorber/ETL and absorber/HTL interfaces. The optimized PSC exhibited a maximum efficiency of 19.30%. These results obtained in this study are expected to contribute considerably to the optimization and efficiency improvement of perovskite solar cells using inorganic charge-carrier transport layers.

Performance evaluation of an eco-friendly and highly efficient FASnI3-based perovskite solar cell using Mg-doped CuCrO2 as HTL

Perovskite-based solar cells have emerged as promising photovoltaic devices. However, challenges involving unstable and toxic materials hinder their commercial use. Addressing these issues, the investigation incorporates a non-toxic tin-based absorber layer and specific inorganic charge transporter materials. The focus is on formamidinium tin iodide (FASnI3) based perovskite solar cells (PSCs), known for their efficiency, lead-free composition, and environmental friendliness. Zinc oxy-sulphide (ZnO0.25S0.75) serves as the electron transport layer (ETL) due to its 3.03 eV band gap. Magnesium doped copper delafossite (Mg–CuCrO2) acts as the hole transport layer (HTL) for its 3.3 eV band gap and its ability to maintain device stability. The proposed structure Au/Mg–CuCrO2/FASnI3/ZnO0.25S0.75/TCO was analyzed using numerical simulation conducted with the solar cell capacitance simulator (SCAPS-1D). Performance parameters of the structure were assessed by varying FASnI3 absorber layer thickness, defect density, and doping concentration. Variations in ETL and HTL thickness, defect density, and electron affinity were also explored. Effects of interface defects, series resistance, shunt resistance, and temperature on the device were examined. The optimized device achieved Voc of 1.2462 V, Jsc of 27.98 mA/cm2, FF of 89.33%, and PCE of 31.16%. This level of efficiency holds significant promise as an alternative for a highly effective environmentally friendly solar absorber material in photovoltaic applications.

Correlation between defect properties and the performance of eco-friendly CsSnI3-based perovskite solar cells

This study investigates the potential use of eco-friendly, all-inorganic cesium tin iodide (CsSnI3) perovskite (PVK) as an absorber layer. Despite having higher temperature stability of CsSnI3, the challenge is to get a uniform and defect-free film that hinders the performance. To accomplish this goal, we investigated several performance-related variables for perovskite solar cells (PSCs), including material defect density (Nt ), transport materials, layer thickness, temperature impacts, and back contact work functions. Negative valence band or conduction band offset values indicate no barrier preventing photogenerated carriers from flowing into the charge transport layers. The simulation result shows that hole transport layer thickness shows a higher impact than electron transport layer thickness. For the PVK thickness of 500 nm and a carrier density of 1018 cm−3, the device offers an optimum power conversion efficiency of 20.1%. The performance is more significantly affected by the defects in the PVK material compared to the defects present at the interface. Higher recombination (Re−h+) occurs at the TiO2–CsSnI3 interface. Defects located within the deep-level trap positioned at the mid-point of the band gap energy (E g) have a negative impact on the performance. The temperature coefficient (C T) is approximately ‒0.367% K‒1, indicating excellent thermal stability in an open environment. The selection of ‘A’ cation, the addition of additives, or carefully controlled fabrication techniques can mitigate the defect. This research shows the strategy for creating defects-free PSC devices, ultimately enhancing performance and the stability.

Comparative study on perovskite solar cells using P_ZnO, Al_ZnO and In_ZnO as ETMs by SCAPS-1D

This study uses the SCAPS 1D software to analyze solar cells with lead iodide perovskite (CH3NH3PbI3) as the active material and three different types of ZnO doping: undoped (P_ZnO), aluminum-doped (Al_ZnO), and indium-doped (In_ZnO) as the electron transport layer (ETL). This study aims to investigate the effects of charge carrier density on the J-V characteristics and electrical properties (Jsc, Voc, FF, Eff) of a solar cell structure made up of FTO/ETL/CH3NH3PbI3/CuInSe2/Au. Gold makes up the back contact, and tin oxide doped with fluorine (FTO) makes up the front contact. These two compounds have work roles are 5.47 eV and 4.4 eV respectively. Zinc oxide, both undoped and doped, makes up the electron transport layer, whereas methyl ammonium lead iodide makes up the absorber layer. Thin sheets, indium diselenide, and copper make up the hole transport layer. An optimal perovskite layer was obtained by decreasing the electron transportation layer's thickness (ETL) from 500 to 100 nm. For the In_ZnO ETL, this optimization was accomplished at 300K working temperature. Reduced ETL thickness was shown to result in higher efficiency (above 27%), as well as higher fill factor (above 87%). With a Voc value of 1.180V, a FF value of 87.55%, and a Jsc value of 26.276mA/cm2, the greatest efficiency performance of 27.15% was found. Using an absorber layer made of CH3NH3PbI3 with a thickness of 800 nm and indium-doped oxide of zinc (In_ZnO) is the layer that transports electrons, this performance was achieved. The results are obtained at a constant irradiance level of 1000 W/m2, under the AM1.5G spectrum.

Targeting high performance of perovskite solar cells by combining electronic, manufacturing and environmental features in machine learning techniques

This study employs Machine Learning (ML) techniques to optimize the performance of Perovskite Solar Cells (PSCs) by identifying the ideal materials and properties for high Power Conversion Efficiency (PCE). Utilizing a dataset of 3000 PSC samples from previous experiments, the Random Forest (RF) technique classifies and predicts PCE as the target variable. The dataset includes various features encompassing cell architecture, substrate materials, electron transport layer (ETL) attributes, perovskite characteristics, hole transport layer (HTL) properties, back contact specifics, and encapsulation materials. ML-driven analysis reveals novel, highly efficient PSC configurations, such as Fe2O3/CsPbBrI2/NiO-mp/Carbon, CdS/FAMAPbI3/NiO–C/Au, and PCBM-60/Phen-NaDPO/MAPbI3/asy-PBTBDT/Ag. Additionally, the study investigates the impact of crucial parameters like perovskite bandgap, ETL thickness, thermal annealing temperature, and back contact thickness on device performance. The predictive model exhibits high accuracy (86.4 % R2) and low mean square error (1.3 MSE). Notably, the ML-recommended structure, SnO2/CsFAMAPbBrI/Spiro-OmeTAD/Au, achieves an impressive efficiency of around 23 %. Beyond performance improvements, the research explores the integration of ML into the manufacturing and quality control processes of PSCs. These findings hold promise for enhancing conversion yields, reducing defects, and ensuring consistent PSC performance, contributing to the advancement of this renewable energy technology.

Exploring the impact of electron transport layer thickness and morphology on perovskite infiltration and photoresponse in HTM-free self-powered photodetector

Methylammonium lead Iodide (MAPbI3) is emerging as the frontrunner for high-performance photo-detection due to its superior optoelectronic characteristics and ease of processing. Titanium dioxide (TiO2) is the commonly employed electron transport layer in conventional perovskite-based photodetectors. However, the fundamental understanding of the role of TiO2 morphology and its thickness on the photodetector performance is yet to be explored explicitly. This work systematically investigates the impact of morphology (mesoporous versus compact TiO2 layer) and thickness of the TiO2 layer (50 nm – 3000 nm) on the MAPbI3 photodetector performance. The devices have been fabricated in a hole transport material (HTM)-free architecture with carbon as the top contact. The heterojunction between MAPbI3 and TiO2 renders the device with self-powered capability. The influence of the perovskite sensitisation in the TiO2 electrodes, carrier recombination characteristics and charge-carrier transfer resistances have been studied using photoluminescence and impedance spectroscopy. The TiO2 layer morphology and thickness affected the MAPbI3 infiltration and film formation kinetics. Impedance and photoluminescence spectroscopies reveal that TiO2 layers, with thickness above 460 nm, negatively affected the device performance. An optimum thickness of 460 nm-mesoporous TiO2 layer exhibited a superior responsivity and rise time of 2.9 A/W and 21 ms, respectively. The poor performance at higher thicknesses is due to the increased interfacial charge transfer resistance and charge carrier recombination. This work is the first report of extensive optimisation and study on the impact of TiO2 film morphology and thickness on the MAPbI3 photodetectors. The present work will be a key for modelling and designing high-performance perovskite photodetectors.

Modelling of Germanium-Based Perovskite Solar Cell for Different Hole Transport Materials and Defect Density

The performance of four distinct materials (organic and inorganic) was simulated and analyzed as hole transport layer (HTL) in the design of germanium (Ge)-based Perovskite Solar Cell (PSC). A 1-dimensional numerical software (SCAPS 1-D) has been applied to simulate the HTL candidates: spiro-OMeTAD, PTAA, nickel oxide (NiO), and copper (I) thiocyanate (CuSCN), with tin (IV) dioxide (SnO2) as the electron transport layer (ETL). The thickness of the methylammonium germanium iodide (CH3NH3GeI3) absorber was varied from 300 nm to 1100 nm, and the highest simulated power conversion efficiency was achieved at a thickness of 800 nm for all HTL candidates. It was observed that the inorganic CuSCN outperformed its counterparts with a power conversion efficiency (PCE) of 25.38%. The effect of the perovskite absorber’s defect density was investigated, and ultimately, it was demonstrated that this value is disproportionately related to the PCE. A reduction of nearly 98% in PCE was recorded when the defect density increased from 1x1014 cm-3 to 1x1020 cm-3. Additionally, for a constant ETL thickness of 80 nm, it was revealed that the PCE would decrease slightly, ranging from 0.1% to 0.3%, with an increase in HTL thickness from 50 nm to 300 nm. Comparing the PCE of our current work with published reports further justifies its competitiveness. Full Text: PDF References W.R. Becquerel, "Becquerel Photovoltaic Effect in Binary Compounds", J. Chem. Phys. 32, 1505 (1960). CrossRef A. Kojima, K. Teshima, Y. Shirai, T. Miyasaka, "Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic Cells", J. Am. Chem. Soc. 131, 6050 (2009). CrossRef M.M. Salah, K.M. Hassan, M. Abouelatta, A. Shaker, "A comparative study of different ETMs in perovskite solar cell with inorganic copper iodide as HTM", Optik 178, 958 (2019). CrossRef S. Rai, B. Pandey, A. Garg, D. Dwivedi, "Hole transporting layer optimization for an efficient lead-free double perovskite solar cell by numerical simulation", Opt. Mater, 121, 111645 (2021). CrossRef H. Liangsheng, Z. Min, S. Yubao, M. Xinxia, W. Jiang, Z. Qunzhi, F, Zaiguo, L. Yihao, H. Guoyu, L. Tong, "Tin-based perovskite solar cells: Further improve the performance of the electron transport layer-free structure by device simulation", Sol. Energy, 230, 345 (2021). CrossRef K. Fatema, M. Arefin, "Enhancing the efficiency of Pb-based and Sn-based perovskite solar cell by applying different ETL and HTL using SCAPS-ID", Opt. Mater. 125, 112036 (2022). CrossRef P. Patel, "Device simulation of highly efficient eco-friendly CH3NH3SnI3 perovskite solar cell", Sci. Rep., 11, 3082 (2021). CrossRef P. Roy, Y. Raoui, A. Khare, "Design and simulation of efficient tin based perovskite solar cells through optimization of selective layers: Theoretical insights", Opt. Mater., 125, 112057 (2022). CrossRef A.I. Azmi, M.Y. Mohd Noor, M.H.I. Ibrahim, F. Ahmad, M.H. Ibrahim, "A Numerical Simulation of Transport Layer Thickness Effect in Tin-Based Perovskite Solar Cell", JJEE, 8, 355 (2022). CrossRef A.A. Kanoun, M.B. Kanoun, A.E. Merad, S. Goumri-Said, "Toward development of high-performance perovskite solar cells based on CH3NH3GeI3 using computational approach", Sol. Energy, 182, 237 (2019). CrossRef A. Hima, N. Lakhdar, "Enhancement of efficiency and stability of CH3NH3GeI3 solar cells with CuSbS2", Opt. Mater., 99, 109607 (2020). CrossRef S.T. Jan, M. Noman, "Influence of layer thickness, defect density, doping concentration, interface defects, work function, working temperature and reflecting coating on lead-free perovskite solar cell", Sol. Energy, 237, 29 (2022). CrossRef

Insight into conduction band density of states at c-Si/TiO2 interface for efficient heterojunction solar cell

Carrier selective solar cell has become one of the hot spots in the area of Si solar cell. The proposed architecture FTO/TiO2/c-Si/i-a-Si:H/Cu2O/back contact studied through simulation demonstrates a power conversion efficiency of 20.03%. This study is the first to report detailed exploration of effect of the conduction band density of states on the efficiency of Si solar cell. Through optimization, the conduction band density of state (1017 cm-3) drastically increases the power conversion efficiency from 18% (at 1021 cm-3) to 21.25% (at 1017 cm-3) i.e., an improvement of 18% relatively. Along with this, the parameters like absorber layer thickness, absorber’s defect density, thickness of electron transport layer and interface defect density are also optimized. Moreover, the charge transport properties and the impact of the Schottky barrier height at c-Si/TiO2 interface on band alignment is studied. After optimization of various physical parameters such as thickness (100 μm), conduction band density of states (1017 cm-3) and defect concentration (1010 cm−3) of c-Si layer, thickness of TiO2 layer (20 nm) and interface defect density at c-Si/TiO2 junction (1010 cm−2), a short-circuit current of 38.11 mA cm−2, open-circuit voltage of 0.84 V, fill factor of 85.99% is obtained, leading to an enhanced theoretical power conversion efficiency of 27.77%.

Modeling and simulation of > 19% highly efficient PbS colloidal quantum dot solar cell: A step towards unleashing the prospect of quantum dot absorber

We used the SCAPS-1D simulation tool to maximize the performance of lead sulfide (PbS) solar cells. A PbS solar cell was first modeled and then experimentally verified from past research. The ZnO electron-transport layer (ETL) was then replaced with ZnO:Al ETL material. Additionally, the fluorine-doped tin oxide work function, PbS-TBAI, ZnO:Al layer thicknesses, ZnO:Al/PbS-TBAI, PbS-TBAI/PbS-EDT defect density, PbS-TBAI defect density, ZnO:Al, and PbS-TBAI doping concentration were optimized. Results showed a greater alignment of the absorber-layer valence band with the HOMO and LUMO of ZnO:Al than that of ZnO ETL. The PbS solar cell exhibited the greatest efficiency at the optimum values of 0.4 µm, 0.04 µm, 1019 cm–3, 4.0 eV, 1017 cm–3, 1014 cm–2, 1018 cm–2, and 3.8 eV for absorber thickness, ETL thickness, ETL doping concentration, work function of front contact, PbS-TBAI doping concentration, and electron affinity of ZnO:Al, respectively. The PbS solar cell also performed best at interface defect densities of 1014 and 1018 cm–2 for ZnO:Al/PbS-TBAI and PbS-TBAI/PbS-EDT, respectively. The PCE of ZnO:Al ETL-based device also increased from 15.036% before optimization to 19.169% after. The optimized result was found to be affected by temperature. The PbS-optimized device with inorganic hole-transport layers (HTLs) demonstrated higher performance than the device with organic HTL. This finding was attributed to the low hole mobility in the organic HTL than those of inorganic ones. Therefore, the ZnO:Al ETL-based device was more efficient than the ordinary ZnO ETL-based device.

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.

P‐162: Late‐News Poster: Analysis of Various solvents for Hole Transport Layer in Tandem Structure Quantum Dot Light Emitting Diode

To achieve high‐resolution display, dual color tandem quantum dot light emitting diodes (QD‐LED) could be candidate. This tandem QD‐LED's characteristics affected by interface of emission layer (EML)/hole transport layer (HTL) and thickness of electron transport layer (ETL). In this research, we analyzed various solvents for HTL and modulated ETL thickness.

Numerical Simulation of Highly Efficient Cs2TiI6 based Pb Free Perovskites Solar Cell with the Help of Optimized ETL and HTL Using SCAPS-1D Software

In order to provide the best photovoltaic application, this paper examines the physical, optical, and electrical aspects of Cesium Titanium (IV) based single halide Perovskite absorption materials. Perovskite solar cell for scavenging renewable energy, has grown more and more necessary in the context of the diversification of the use of natural resources. Due to its efficient band gap of 1.8 eV, Cs2TiI6 has become a desirable contender for today's thin-film solar cell. This article shows the spectrum responses of a planar Au/FTO/C60/Cs2TiI6/CH3NH3SnI3/Al based structure where CH3NH3SnI3 is used as a Hole transport layer (HTL) and C60 and FTO are utilized as Electron transport layers (ETL) under 300K temperature conditions. This research demonstrates that employing FTO and C60 as Electron transport layer charge extraction can be achieved. FTO provides High transmission, strong conductivity, and good adherence for the deposited layers. When used in a coevaporated perovskite solar cell, a C60 layer with an ideal thickness less than 15 nm improves charge extraction. This article tried to avoid cadmium for solar cell generation due to its toxicity on environment. The simulation included detailed configuration optimization for the thickness of the absorber layer, HTL, ETL, defect density, Wavelength, temperature, and series resistance. In this work the Power Conversion Efficiency (η), Fill Factor (FF), Open-circuit Voltage (Voc), J-V Curve, Quantum Efficiency and Short-circuit current (Jsc) have been measured by varying thickness of absorber layer in the range of 1µm to 6 µm. The optimized perovskite solar cell shows a power conversion efficiency of 21.8429% when the absorber layer thickness is 4µm and electron transport layer thickness is 0.6µm.

Design of an eco-friendly perovskite Au/NiO/FASnI3/ZnO0.25S0.75/FTO, device structure for solar cell applications using SCAPS-1D

Formamidinium Tin Iodide (FASnI3) based perovskite solar cells (PSC) have captured the interest of scientific community because of wide bandgap and good thermal stability, but limited power conversion efficiency (PCE) restricts their extensive adaptation. Here, we present the design of a FASnI3 active layer-based PSC with Nickel oxide (NiO) as Hole Transport Layer (HTL) & Zinc Oxy-Sulphide (ZnO0.25S0.75) as the Electron Transport Layer (ETL). The proposed Au/NiO/FASnI3/ZnO0.25S0.75/FTO, device structure is investigated using SCAPS-1D solar cell capacitance simulator. The performance parameters of proposed solar cells device structure are investigated with variations in active layer (FASnI3) thickness, defect density & doping concentration; and variations of NiO HTL & ZnO0.25S0.75 ETL thickness, electron affinity & doping concentration to obtain higher performance. Moreover, the influence of series & shunt resistance, and temperature on the performance parameters of proposed solar cell device structure is inspected. The proposed Au/NiO/FASnI3/ZnO0.25S0.75/FTO, device structure revealed excellent solar cell performance parameters such as low short-circuit current density (Jsc) of ∼28.35 mA/cm2, high Fill Factor (FF) of ∼89.64%, reasonable open-circuit voltage (Voc) of ∼1.2419 V, & admirable PCE of ∼31.57%, suitable for lead-free and eco-friendly solar cell device applications.

Numerical analysis of Al/Gr/ETL/MoS2/Sb2S3/Ni solar cell using non-toxic In2S3/SnS2/ZnSe electron transport layer

In this study, Molybdenum disulfide (MoS2) based thin film solar cells (TFSCs) of the structure Al/Gr/ETL/MoS2/Sb2S3/Ni have been simulated using SCAPS-1D software. Due to their remarkable properties, three Cd-free and non-toxic (In2S3, SnS2, and ZnSe) electron transport layer (ETL) materials were suggested for MoS2-based TFSCs. The effect of various layer parameters on the performance of the cells was investigated for various ETL materials. The considered parameters are the MoS2 absorber layer thickness, the carrier density and thickness of the ETL, and the ETL/MoS2 interface defect density, as well as the impact of the working temperature, series resistance, and shunt resistance. The simulation results show that the highest power conversion efficiency is achieved for the MoS2 absorber layer thickness of 1.0 µm, and the thickness and carrier density of different ETLs of 0.05 µm and 1016 cm-3, respectively. We found that the defect density of the ETL/MoS2 interface should be controlled under 1012 cm-2. The optimized power conversion efficiencies of MoS2-based TFSCs are found by simulation 27.88%, 28.22%, and 28.29% for the cell with In2S3, SnS2, and ZnSe ETL, respectively. Among the three ETL materials used, zinc selenide (ZnSe) shows the best results due to its wider band gap. We have found that the cells with the FTO window layer show slightly better performance than those with the graphene. Maximum photovoltaic efficiency of 28.54% has been achieved for the solar cell of the structure Al/FTO/ZnSe/MoS2/Sb2S3/Ni. The results of simulations reveal that high-efficiency MoS2 solar cells with non-toxic (In2S3, SnS2, and ZnSe) ETLs can be obtained. Overall, the numerical simulation conducted in this study could contribute to the manufacture of Cd-free non-toxic and highly efficient MoS2-based solar cells.

Effect of the Electron Transport Layer Thickness on I–V Characteristics of the S-Shaped Kinks in Perovskite Solar Cells

In our experimental preparation of perovskite solar cells (PSCs), when the thickness of the electron transport layer (ETL) was changed from thin to thick, the current–voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{I}$</tex-math> </inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{V}$</tex-math> </inline-formula> ) characteristics showed the changing laws of S-shaped kinks appearance, S-shaped kinks disappearance, and S-shaped kinks appearance. A lumped-parameter equivalent circuit model is proposed to reveal the intrinsic physical significances of the S-shaped kinks for this variation laws. The explicit solution of the model is derived using the deformed difference-microvariation (DM) principle combined with the region method, and the model parameters are extracted efficiently through the firefly optimization algorithm (FA). The proposed analytical solution enables the model to be compactly implemented in photovoltaic devices and circuit simulators, and the model is expected to point the direction for process optimization of devices.