Performance evaluation of lead free CH3NH3SnI3/GeTe Tandem solar cell with HTL layer by SCAPS 1D

Abstract

In this article, with the help of a one dimensional solar cell simulator, we have assessed different performance parameters of a lead free CH3NH3SnI3/GeTe Tandem solar cell. The performance parameters in terms of open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF) and photo conversion efficiency (PCE) have been investigated for different thickness of absorber layer, acceptor concentration, defect density and series/shunt resistance and compared with a single junction solar cell. Incorporation of GeTe as a secondary absorber layer improves the performance of the solar cell by increasing photon absorption rate. Using Cu2O as a hole transport layer, formation of a quantum well takes place which further enhances the photon absorption rate and hence solar cell performance. The optimized tandem cell with hole transport layer shows 28 %, 9 %, 19 % and 12 % improvement in Voc, Jsc, FF and PCE compared to the single junction solar cell without hole transport layer.