Comparative Simulation Study of the Performance of Conventional and Inverted Hybrid Tin-Based Perovskite Solar Cells

A hybrid tin-based (GA0.2FA0.78SnI3-1% EDAI2) perovskite solar cell (PSC) with a p-i-n inverted structure has been reported to pass all the rigorous standard tests successfully and achieve a certified power conversion efficiency (PCE) of 8.3%. Our previous numerical study showed that this PCE could be considerably increased to 24.1% by engineering and controlling the interfaces of the cell. The aim of the current study is to compare the performance of a conventional n-i-p structure with its inverted p-i-n analog quantitatively, and demonstrate that, by improving the conventional structure, it can achieve a PCE score approximately equal to the inverted p-i-n structure. To that end, the absorber layer was chosen to be GA0.2FA0.78SnI3-1% EDAI2, while four ETL (electron transport layer) materials (TiO2, WS2, SnO2, and ZnOS), and four HTL (hole transport layer) materials (PEDOT:PSS, Cu2O, CuSCN, and CuI) were considered. Most used ETL/HTL combinations have been rigorously investigated with the aim of finding the ultimate configuration, providing the highest photovoltaic properties. Additionally, the effect of the layers’ thicknesses and their doping concentrations were inspected, and their impact on the photovoltaic properties of the PSC was investigated. The optimized structure with CuI (copper iodide) as the HTL and ZnOS (zinc oxysulphide) as the ETL scored a PCE of 24.1%, which is comparable to the value found with the inverted structure (26%). The current numerical simulation on GA0.2FA0.78SnI3-1% EDAI2 could be considered as a milestone in its chances for commercial development.