Enhanced Charge Separation Efficiency Accelerates Hydrogen Evolution from Water of Carbon Nitride and 3,4,9,10-Perylene-tetracarboxylic Dianhydride Composite Photocatalyst.

The catalytic ability of graphitic carbon nitride is greatly affected by its intrinsic electronic properties. Although combination with chromophore has been demonstrated to be one of the promising approaches to improve the catalytic performance of carbon nitride, it is imperative to understand the key factors governing the whole process. Here, we report a composite photocatalyst CN-P by embedding perylene unit into the matrix of carbon nitride. The composite photocatalyst could catalyze hydrogen evolution with a high rate of 17.7 mmol h-1 g-1, which is 2.8 times faster than pure carbon nitride. The apparent quantum efficiency is high up to be 5.8% at 450 nm. Detailed studies reveal that the light absorption ability and charge separation efficiency are greatly enhanced in the synthesized catalyst. These are the key factors for the improved hydrogen evolution ability of CN-P than that of pure carbon nitride.