Dual‐function interface engineering for efficient perovskite solar cells

Interface engineering has been proven a powerful tool to improve performances of the perovskite solar cells (PSCs). Herein, highly π-conjugated graphdiyne (GDY) is employed as an interface linker between film and hole transport layer (HTL). It found that GDY can significantly suppress formation metallic Pb (a detrimental defect), reduces carrier recombination. The also form π-π stacking interaction with HTL, facilitates collection photogenerated holes. perovskite/GDY/HTL combination leads large improvement in both power conversion efficiency (from 19.94% 22.17%) device stability. In addition, applied 3D/2D PSCs, outstanding PCE 23.42% achieved.