One-pot surface and buried interface manipulation of perovskite film for efficient solar cells

Reducing the defects located at the interfaces between the perov-skite layer and charge transport layers is critical to improving the ef-ficiency and stability of perovskite solar cells (PSCs). However, it is difficult to manipulate both interfaces simultaneously with synergis-tic beneficial effects. Here, we report a strategy of one-pot surface and buried interface manipulation of 3D perovskite films by intro-ducing two diammonium Ni and Cu porphyrins. The Ni porphyrin (NiP) and Cu porphyrin (CuP) act as bulky cations to yield 2D perov-skite layers at the top-buried interfaces of 3D perovskites. The porphyrin-based 2D perovskite layer facilitates charge transport significantly suppressing non-radiative recombination. The device based on CuP&NiP manipulation yields an improved efficiency of up to 24.2% along with long-term overall stability. This work pro-vides an approach for one-pot surface and buried interface manipu-lation of perovskite films by functional porphyrins to improve the efficiency and stability of PSCs.