Optimization of formamidinium-based perovskite solar cell using SCAPS-1D

Perovskite materials have recently emerged as promising candidates as an absorber layer in solar cells. In this study, the photovoltaic performance of a formamidinium lead iodide perovskite (FAPbI3) based solar cell is assessed and improved by optimizing the thickness of the active layer using the Solar Cell Capacitance Simulator (SCAPS-1D) software. The architecture of the solar cell analyzed is a conventional planar n-i-p type composed of fluorine-doped tin oxide (FTO) as the front contact, tin oxide (SnO2) as the electron transport layer (ETL), FAPbI3 as the absorber layer, lithium bis(trifluoromethylsul-phonyl)imide (LiTFSI) doped spiro-OMeTAD as the hole transport layer (HTL), and silver (Ag) as the back contact. The simulation was carried out with and without parasitic resistances. The efficiency of the ideal device was 20.95 % when absorber thickness was between 0.68 µm and 0.78 µm and 14.45 % for the non-ideal device when the series resistance Rseries= 10 Ω·cm2 and shunt resistance Rshunt= 5000 Ω·cm2. We have found that the PCE of the original non-ideal device can be increased by 26 % through optimization of layer thickness and carrier transport.