Uncontrolled Ostwald maturation is often accompanied by residual lead iodide (PbI2), which can degrade into elemental lead and severely damage the perovskite device upon exposure to light and radiation, ultimately accelerating device decay. However, PbI2 also serves as a critical raw material for the formation of a two-dimensional perovskite. Herein, we designed an innovative synergistic passivation strategy that effectively utilized residual PbI2 generated during Ostwald ripening as a raw material for dimensional engineering, achieving deep passivation for defects and improving the performanc...
