Over 26% and 24%-Efficiency Rigid and Flexible Perovskite Photovoltaics through Enhanced Crystallinity and Alleviated Residual Strains

The realization of the perovskite with few ionic defects, high crystallinity, and alleviated residual strains is crucial for making efficient rigid and flexible perovskite solar cells (PSCs). Herein, we used a passivating agent of 3-methylthio-1,2,4-triazine with strong anchoring strengths to passivate defects of the perovskite. This buried interface passivation improved the crystallinity of the perovskite with an alleviated residual strain while eliminating the localized deep-level defect states, thereby reducing the nonradiative recombination and minimizing the charge transport losses. The rigid and flexible PSCs delivered power conversion efficiencies of 26.04 and 24.16%, respectively. The rigid PSCs exhibited improved operational stability, and the flexible PSCs showed enhanced bending stability. The research provides insights into the enhancement in efficiency, operational stability, and bending stability of the perovskite photovoltaics.