Three-dimensional porous g-C3N4 for highly efficient photocatalytic overall water splitting

Herein, this work constructs a three-dimensional porous graphitic carbon nitride assembled by highly crystalline and ultrathin nanosheets (3D g-C3N4NS). 3D g-C3N4NS could directly split pure water into H-2 and O-2 with high evolution rate up to 101.4 and 49.1 mu mol g(-1) h(-1) under visible light, respectively, approximately 11.8 and 5.1 times higher than bulk g-C3N4 and g-C3N4NS. Besides, it achieves a notable apparent quantum yield of 1.4% at 420 nm, significantly superior to previously reported Pt/g-C3N4. The efficient activity of 3D g-C3N4NS is mainly attributed to its 3D interconnected open-framework, assembled by highly crystalline ultrathin nanosheet unit, provides a pathway for faster charge carrier transport. Moreover, benefitting from its 3D structure for preventing agglomeration of nanosheets, 3D g-C3N4NS is stable for more than 100 h of overall water splitting reaction.