Optimizing perovskite solar cells: simulating the impact of Bi₂Te₃ and BiTeI interlayers

Abstract Perovskite solar cells (PSCs) have emerged as a promising technology for efficient and cost-effective solar energy conversion. To further enhance their performance and stability, integrating interlayer (IL) between the perovskite absorber and transport layers is paramount. In this study, we investigated and compared the performance of two distinct IL materials, Bi 2 Te 3 (BT) and BiTeI (BTI), in PSCs. The ILs were integrated between the perovskite layer and electron/hole transport layers to modulate charge transport and recombination dynamics. Our results reveal that both BT and BTI ILs can effectively passivate the surface defects in the perovskite absorber, leading to reduced non-radiative recombination and improved open-circuit voltage (V OC ) in the solar cells. The thickness of the BT and BTI IL was varied from 50 nm to 300 nm to study the effect of thickness on the efficiency of the PSC. IL defect density and interface defect densities were also studied in both the PSCs.