Closing the gap between rigid and flexible substrate: optimized route toward reproducible and stable flexible perovskite solar cells

Flexible perovskite solar cells (PSCs) show promise for next-gen photovoltaics, but achieving stability remains challenging, especially between rigid and flexible substrates. This study optimizes flexible PSCs' stability and reproducibility by selecting substrates, refining cleaning processes, and enhancing interfaces. Evaluating various substrates for flexibility, roughness, and perovskite compatibility, a meticulous cleaning protocol removes contaminants, improving perovskite-adhesive interactions. Emphasis on buried interfaces minimizes defects and boosts charge transport. Results show improved PSC efficiency (15.2% to 19.7%) and cycle durability (130 to 850 cycles, bending radius 5mm, reaching T80). Closing the performance gap, these findings advance reliable flexible PSCs for portable electronics, wearables, and building-integrated photovoltaics.