Advances in Elemental Doping of Polymeric Carbon Nitride Toward Enhanced Solar‐To‐Hydrogen Conversion

Polymeric carbon nitride (PCN) is a promising visible light photocatalyst for water splitting, yet its intrinsic limitations—restricted light absorption, poor charge separation, and sluggish surface kinetics—limit performance. Elemental doping has emerged as an effective strategy to tailor PCN's electronic structure and accelerate reaction dynamics. This review highlights recent advances in doped PCN, focusing on strategies to enhance light harvesting, promote charge separation, and boost surface reactions, and discusses remaining challenges and prospects for the rational design of high‐performance PCN‐based photocatalysts for efficient solar‐to‐hydrogen conversion.