“…Currently, additive engineering has been regarded as a potential approach for fabricating high-quality polycrystalline films, which would regulate the crystallization rate and reduce cation/anion vacancy and Pb-related defects by virtue of delaying nucleation and suppressing the nonradiative recombination in PSCs. − Among numerous additives, graphitic carbon nitride (g-C 3 N 4 ) has attracted great attention due to its low cost, facile synthesis, and excellent thermal and chemical stability advantages. − For example, Jiang and co-workers incorporated g-C 3 N 4 perovskite films and found they can slow down the crystallization process, which enhances the grain size and improves light-harvesting properties . In addition, g-C 3 N 4 can also passivate the uncoordinated Pb 2+ , which reduces the trap density in the perovskite film to suppress nonradiative recombination loss and minimize the moisture permeation to improve the stability of the perovskite material. − However, g-C 3 N 4 itself has drawbacks such as poor conductivity and limited types of functional groups, , which still has room to improve its conductivity and defect passivation ability via appropriate optimization.…”