Performance Enhancement of Aluminum doped ZnO based Lead-free Perovskite Solar Cell

Abstract

Lead halide based perovskite solar cells achieve a promising efficiency which exceeds 20%. However, due to the toxicity of lead it is unsuitable for wide application. Rather, lead-free absorber, CH₃NH₃SnI₃ is a preferable choice for solar energy harvesting. In this work, a numerical analysis is presented for a planar PSC structure with CH₃NH₃SnI₃ as an absorber, CH₃NH₃SnBr₃ as a hole transporting layer and aluminum-doped zinc oxide as an electron transporting layer. The performance evaluation is done by varying the thickness and defect density of the absorber layer as well as the doping densities of the charge carrier transporting layers. The optimum thickness and defect density of the absorber layer are obtained to be 800 nm and 10¹³ cm⁻³, respectively. The optimum doping density for the charge carrier transporting layers is 10²¹ cm⁻³, After optimization, the final cell efficiency is found to be 19.34%.