Performance optimization of inorganic thin film perovskite solar cell with visible-light active chalcogenide photocatalysts as electron transport layer

In solar cell research, inorganic lead-free metal halide-based perovskites have recently attracted considerable interest because of their rapid increase in power conversion efficiency (PCE), and the integral toxicity and instability of lead in perovskite solar cells (PSCs). Implementation of these materials convey multiple benefits, including improved resistance to degradation, decreased cost, and reduced recombination rate of carriers. However, the performance of a PSC can be substantially improved through the appropriate selection of electron transport layer (ETL). The ETL of a heterojunction perovskite solar cell is essential for efficient charge extraction and transport within the structure. Additionally, it improves light absorption, enhances durability, reduces production costs, increases stability, hence, elevates the overall cell performance and PCE. In this study, the impact of visible-light active chalcogenides as ETLs was numerically assessed through the development of a PSC device composed of Glass/FTO/ETL/Perovskite/HTL/Ni structure, using SCAPS-1D. The perovskite material utilized in this study is CsSnI 3 , while the various electron transport layers (ETLs) are CdS, CdSe, ZnSe, In 2 S 3 , and MoS 2 , respectively. The hole transport layer (HTL) is Cu 2 O; and Ni is used as back contact material. To achieve maximum efficiency, each of the five PSC devices was tuned and optimized by adjusting several parameters, including the thickness of the absorber layer and ETL, the acceptor density of the absorber and donor density of the ETL, as well as the defect densities of both the ETL and absorber, and the interface defect densities. Superior performance was achieved by the FTO/CdS/CsSnI 3 /Cu 2 O/Ni and FTO/ZnSe/CsSnI 3 /Cu 2 O/Ni structures with a maximum PCE of 28.86 %, V OC of 0.855 V, J SC of 62.764 mA/cm 2 , FF of 53.58 % for the first device, and PCE of 26.41 %, V OC of 0.834 V, J SC of 57.688 mA/cm 2 , FF of 54.93 % for the second. The analytical data recorded in this extensive study will serve as an important guide to selecting the optimal ETL materials for perovskite solar cells, enabling the production of high-performance lead-free PSC devices. • Visible-light active chalcogenides as ETLs on a Pb-free PSC performance is evaluated. • Effect of CdS, ZnSe, MoS 2 , In 2 S 3 , and CdSe is investigated by SCAPS-1D simulation. • ZnSe, MoS 2 , and In 2 S 3 exhibit remarkable performance as alternatives of CdS. • Optimized PCEs are: 26.41 % (ZnSe), 20.92 % (MoS 2 ) and 18.25 % (In 2 S 3 ).