The power conversion effciency (PCE) of flexible perovskite solar cells (PSCs) has increased rapidly, while the mechanical flexibility and environmental stability are still far from satisfactory. Previous studies show the environmental degradation and ductile cracks of perovskite films usually begin at the grain boundaries (GBs). Herein, sulfonated graphene oxide (s-GO) is employed to construct a cementitious GBs by interacting with the [PbI₆]^4– at GBs. The resultant s-GO-[PbI₆]^4– complex can effectively passivate the defects of vacant iodine, and the devices with s-GO exhibit remarkable waterproofness and flexibility due to the tough and water-insoluble GBs. The champion PCE of 20.56% (1.01 cm²) in a device treated with s-GO is achieved. This device retains 90% of its original PCE after 180 d stored in the ambient condition, as well as over 80% retention after 10,000 bending cycles at a curvature radius of 3 mm.

柔性钙钛矿太阳能电池（PSC）的功率转换效率（PCE）迅速提高，而机械柔韧性和环境稳定性仍远未令人满意。先前的研究表明，钙钛矿薄膜的环境退化和延展性裂纹通常始于晶界 (GBs)。在此，磺化氧化石墨烯 (s-GO) 通过与 GBs 处的 [PbI ₆ ] ^4–相互作用来构建水泥基GBs。所得的 s-GO-[PbI_{​​ 6} ] ^4–络合物可以有效钝化碘空位的缺陷，并且由于坚韧且不溶于水的 GB，具有 s-GO 的器件表现出显着的防水性和柔韧性。20.56% (1.01 cm ²) 在用 s-GO 处理的设备中实现。该器件在环境条件下存放 180 天后仍保留其原始 PCE 的 90%，在曲率半径为 3 mm 的情况下经过 10,000 次弯曲循环后仍保留超过 80%。