Investigation of impact of kesterites as hole transport layer on (FA)2BiCuI6 based ecofriendly double perovskite solar cell to obtain optimized PCE above 25%

This paper presents a detailed study of double perovskite (FA)₂BiCuI₆ based perovskite solar cells(PSC) using different kesterites as hole transport layers (HTL) and titanium-based electron transport layers (ETL). The designed double perovskite PSC utilized ${TiO}_2$ as an ETL, different kesterite materials (CZTSe, CFTS, CBTS, CMTS, CNTS and CZTS) as the HTL, double perovskite material (FA)₂BiCuI₆ as the perovskite absorption layer (PAL), Indium tin oxide (ITO) as top electrode and Au as an anode. The different parameters of architecture (ITO/TiO₂/(FA)₂BiCuI₆/HTL/Au) is improved via the SCAPS-1D simulator by first optimizing thickness and then the defect density of PAL. Energy band matching of the different layers with (FA)₂BiCuI₆ is thoroughly investigated in order to understand its operation. AM 1.5G illumination is used as input light source. To obtain optimum performance of (FA)₂BiCuI₆ based PSC the effects of optical thickness, defect density, temperature, series resistance, and shunt resistance are monitored. Among all the kesterites, CNTS based PSC performed extraordinarily well with PCE of 26.09 %. J_SC 22.64 mA/cm², V_OC 1.38 V, FF 83.33 %, and the variables influencing solar cell performance are clarified by simulations. The findings presented in this work will aid researchers in the production of ecofriendly solar cells with great efficiency.