Theoretical study of lead-free perovskite solar cell using ZnSe as ETL and PTAA as HTL

Cesium tin germanium triiodide (CsSn0.5Ge0.5I3) is one of the proficient inorganic halides the perovskites for better stability that has received wide attention in recent years. In the present study, a lead-free perovskite solar cell structure is designed with Zinc selenide as the electron transport layer (ETL), CsSn0.5Ge0.5I3 as the perovskite absorber layer, and PTAA [Poly(bis[4-phenyl]{2,4,6-trimethylphenyl}amine)] as the hole transport layer (HTL). For a more practical understanding of the solar cell, several parameters such as absorber thickness, defect density, doping concentration of absorber layer, interface defects, and working point temperature have been examined. SCAPS-1D simulator is used for the analysis of the proposed device. The PCE of the device has been obtained as 23.15% with VOC = 1.07 V, JSC = 27.24 mA/cm2, FF = 78.82 % at 800 nm thickness of CsSn0.5Ge0.5I3 absorber layer. Selecting the best material parameters and easy fabrication is suitable for developing highly efficient and environmentally friendly perovskite solar cells.