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

Reducing the defects located at the interfaces between the perovskite layer and charge transport layers is critical to improving the efficiency and stability of perovskite solar cells (PSCs). However, it is difficult to manipulate both interfaces simultaneously with synergistic beneficial effects. Here, we report a strategy of one-pot surface and buried interface manipulation of 3D perovskite films by introducing two diammonium Ni and Cu porphyrins. The Ni porphyrin (NiP) and Cu porphyrin (CuP) act as bulky cations to yield 2D perovskite 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 provides an approach for one-pot surface and buried interface manipulation of perovskite films by functional porphyrins to improve the efficiency and stability of PSCs.