Exploring the Effect of Kesterites and Zinc‐Based Charge Transport Materials on the Device Performance and Optoelectronic Properties of FAPbI₃ Perovskite Solar Cells

Formamidinium lead triiodide (FAPbI 3 )‐based perovskite solar cells (PSCs) have shown greater structural stability but lower power conversion efficiency (PCE) than other established perovskites. The efficiency of the PSC can be improved by identifying suitable charge transport layers for FAPbI 3 , having good conductivity, and wide bandgap. Kesterite materials belonging to the adamantine family of chalcogenides are quaternary compounds with high conductivity and tunable bandgap. They have shown excellent results when employed in thin films and hence have emerged as an alternate option to be used for the hole transport layers (HTL). Similarly, zinc‐based materials have remarkable properties in terms of their wide bandgap, inability to oxidize, and abundance, making them a viable option to be explored as electron transport layers (ETL). Herein, six different kesterits are used as HTL to simulate FAPbI 3 PSC with four different zinc‐based ETL. Henceforth, a total of 24 structures is modeled and optimized using SCAPS‐1D. The effect of these materials on the optical absorption, quantum efficiency, electric field, I – V characteristics, and recombination is studied. Among all the structures, CBTS/FAPbI 3 /CdZnS is found to be the best‐performing PSC structure with PCE of 28.55%, short‐circuit current of 26.8 mA cm −2 , open‐circuit voltage of 1.19 V, and fill factor of 88.93%.