Amorphous (lysine) 2 PbI 2 layer enhanced perovskite photovoltaics.

Passivation materials play a crucial role in a wide range of high-efficiency, high-stability photovoltaic applications based on crystalline silicon and state-of-the-art perovskite materials. Currently, for perovskite photovoltaic, the mainstream passivation strategies routinely rely on crystalline materials. Herein, we have invented a new amorphous (lysine) 2 PbI 2 layer-enhanced halide perovskite. By utilizing a solid phase reaction between PbI 2 and lysine molecule, an amorphous (lysine) 2 PbI 2 layer is formed at surface/grain boundaries in the perovskite films. The amorphous (lysine) 2 PbI 2 with fewer dangling bonds can effectively neutralize surface/interface defects, achieving an impressive efficiency of 26.27% (certified 25.94%). Moreover, this amorphous layer not only reduces crystal lattice stress but also functions as a barrier against the decomposition of organic components, leading to suppressed de-structuring of perovskite and highly stable perovskite solar cells.