Enhancing the efficiency of non toxic perovskite solar cell through Cs₄CuSb₂Cl₁₂ as interface layer using SCAPS-1D

Abstract In recent years, Perovskite solar cells (PSC) have showed promising results to substitute traditional PV technologies due to impressive power conversion efficiency (PCE) and cost-effective production. This study investigates the impact of introducing a Cs4CuSb2Cl12 (CCSC) perovskite quantum dot (PQD) interface layer among active layer and hole transport layer (HTL) in CsGeI3 as well as MAGeI3-based PSCs. It aims in enhancing the function of interface layer (IL) by improving PCE while reducing interface losses. TiO2 and Spiro-OMeTAD were employed as the electron transport layer (ETL) and HTL, respectively. SCAPS-1D software was utilized for simulating JSC, VOC, FF, and PCE of various configurations, including passivated and non-passivated structures. The results revealed a substantial increase in JSC from 13.22 mA cm−2 to 15.5 mA cm−2 and PCE from 11.67% to 14.81% for MAGeI3-based PSCs with incorporated PQD layer. Additionally, the fill factor (FF) improved from 50.55% to 76.90%. However, a decrease in VOC from 1.7 V towards 1.24 V was noticed, this was associated with the formation of an energy barrier at HTL/ absorber. For CsGeI3-based devices, a slight improvement in JSC was observed from 21.0 mA cm−2 to 21.8 mA cm−2, whereas VOC remained constant at 1.24 V. The PCE increased from 22.50% to 23.09%, but the FF decreased from 86.83% to 85.48%. However the decrease in the fill factor (FF) may be attributable to a rise in the cell series resistance due to the additional interface, which could impede charge transport and extraction. This simulation study demonstrates that the incorporation of a CCSC PQD IL among active layer / HTL can enhance the PCE and short circuit current of CsGeI3 and MAGeI3-based PSCs, providing a promising avenue for future optimizations and advancements in PSC technologies.