Enhanced Stability and Performance of Perovskite Solar Cells through a Multi-Layered Design with Optimized Transport and Interfacial Layer

Perovskite solar cells (PSCs) are emerging as strong alternatives to silicon photovoltaics due to their low cost, simple fabrication, and wide applicability. Yet, their commercial deployment is hindered by poor stability under heat, moisture, and UV exposure, which degrades device lifetime. This study proposes a multi-layer PSC design to overcome these challenges by integrating optimized materials for enhanced stability and efficiency. The hole transport layer (HTL) employs Cu₂O doped with selenium and tellurium, boosting charge mobility and reducing interfacial defects. A BiI₃ interfacial layer further facilitates charge extraction while minimizing recombination. WS₂ is introduced as the electron transport layer (ETL), enabling efficient electron flow and reducing structural strain. For the absorber, a mixed-halide FA₀.₈₅Cs₀.₁₅Pb(I₀.₈₅Br₀.₁₅)₃ perovskite is used, combining high light absorption with thermal stability. Simulations confirm that this multi-material strategy enhances both power output and resilience, presenting a viable route for durable, next-generation PSCs.