Bridging the g-C 3 N 4 Interlayers for Enhanced Photocatalysis

作者：Ting Xiong, Wanglai Cen, Yuxin Zhang, Fan Dong · 发表于：ACS Catalysis · 年份：2016 · DOI：10.1021/acscatal.5b02922 · 被引用次数：1163 · 研究领域：Advanced Photocatalysis Techniques、Perovskite Materials and Applications、2D Materials and Applications

Graphitic carbon nitride (g-C 3 N 4 ) has been widely investigated and applied in photocatalysis and catalysis, but its performance is still unsatisfactory. Here, we demonstrated that K-doped g-C 3 N 4 with a unique electronic structure possessed highly enhanced visible-light photocatalytic performance for NO removal, which was superior to Na-doped g-C 3 N 4 . DFT calculations revealed that K or Na doping can narrow the bandgap of g-C 3 N 4 . K atoms, intercalated into the g-C 3 N 4 interlayer via bridging the layers, could decrease the electronic localization and extend the π conjugated system, whereas Na atoms tended to be doped into the CN planes and increased the in-planar electron density. On the basis of theoretical calculation results, we synthesized K-doped g-C 3 N 4 and Na-doped g-C 3 N 4 by a facile thermal polymerization method. Consistent with the theoretical prediction, it was found that K was intercalated into the space between the g-C 3 N 4 layers. The K-intercalated g-C 3 N 4 sample showed increased visible-light absorption, efficient separation of charge carriers, and strong oxidation capability, benefiting from the narrowed band gap, extended π conjugated systems, and positive-shifted valence band position, respectively. Despite that the Na-doped g-C 3 N 4 exhibited narrowed bandgap, the high recombination rate of carriers resulted in the reduced photocatalytic performance. Our discovery provides a promising route to manipulate the photocatalytic activity si...