Graphitic C 3 N 4 -Confined B Enables Bifunctional Lattice N Atoms for Photocatalytic CH 4 Conversion

High Resolution Image Download MS PowerPoint Slide The photocatalytic conversion of CH 4 and O 2 to C1 oxygenates represents a promising route for chemical synthesis, yet current systems predominantly depend on metal-based catalysts to achieve efficient light harvesting and charge separation. Herein, we report a metal-free alternative using boron confined within g-C 3 N 4 (B/C 3 N 4 ), which achieves a C1 oxygenates production rate of 28.1 μmol g cat. –1 h –1 with a 60% improvement in activity compared with pristine g-C 3 N 4 . Combined experimental and theoretical investigations reveal that boron confinement in g-C 3 N 4 induces orbital delocalization, which enhances charge carrier separation and creates dual-functional nitrogen sites that facilitate CH 4 oxidation and O 2 reduction reactions. Delocalized nitrogen sites with the lowest unoccupied molecular orbital are responsible for reducing O 2 to •OH radicals, whereas counterparts with the highest occupied molecular orbital facilitate the oxidation of CH 4 to •CH 3 radicals. The resulting •OH radicals can either oxidize CH 4 to generate •CH 3 or directly combine with transient •CH 3 radicals, initiating a cascade reaction that sequentially yields CH 3 OH, HOCH 2 OH, and HCOOH.