Synthesis of Leaf‐Vein‐Like g‐C₃N₄ with Tunable Band Structures and Charge Transfer Properties for Selective Photocatalytic H₂O₂ Evolution

Photocatalytic H 2 O 2 evolution through two‐electron oxygen reduction has attracted wide attention as an environmentally friendly strategy compared with the traditional anthraquinone or electrocatalytic method. Herein, a biomimetic leaf‐vein‐like g‐C 3 N 4 as an efficient photocatalyst for H 2 O 2 evolution is reported, which owns tenable band structure, optimized charge transfer, and selective two‐electron O 2 reduction. The mechanism for the regulation of band structure and charge transfer is well studied by combining experiments and theoretical calculations. The H 2 O 2 yield of CN4 (287 µmol h −1 ) is about 3.3 times higher than that of pristine CN (87 µmol h −1 ), and the apparent quantum yield for H 2 O 2 evolution over CN4 reaches 27.8% at 420 nm, which is much higher than that for many other current photocatalysts. This work not only provides a novel strategy for the design of photocatalyst with excellent H 2 O 2 evolution efficiency, but also promotes deep understanding for the role of defect and doping sites on photocatalytic activity.