Multicomponent Approach for Stable Methylammonium-Free Tin-Lead Perovskite Solar Cells

Abstract

Mixed tin-lead perovskites suffer from several degradation pathways that hinder their effective implementation in tandem photovoltaic technologies. The main challenge involves removing the thermally unstable methylammonium cation from the perovskite composition and simultaneously increasing the oxidation resistance of the tin-based material. This study employs a multicomponent approach to address these issues, developing methylammonium-free tin-lead perovskite solar cells with improved efficiency and stability. The incorporation of cations that tune precursor solution properties enhances the quality of MA-free perovskite films, while reducing agents and surface engineering techniques enhance robustness and carrier dynamics. Consequently, the methylammonium-free perovskite solar cells achieve over 22% efficiency and demonstrate significantly enhanced stability, with minimal losses after over 700 h of continuous operation under 1 sun illumination. This work evidences the potential of comprehensive strategies to process fragile materials, such as tin-containing perovskites, with improved quality and brings them closer to successful broad applications.