Controllable construction 2D-CN photocatalyst for degradation MBT and mechanism insights

A nonmetal two-dimensional carbon nitride (2D-CN) with different thickness is constructed via the facile hydrothermal (adjusting the solution pH to 4.0, 7.0 and 10.0) and calcination method. The 2D-CN-7.0 displays the dramatically enhanced photocatalytic activity (82%) for degrading 2-mercaptobenzothiazole (MBT), originating from the ultrathin 2D structural improved transfer efficiency of charge carriers, greatly decrease the diffusion path of electrons/holes to MBT, accelerating the reaction rate. More importantly, we find that there are no rules can be followed between the band gap and the thickness of CN by density functional theory (DFT) computation theoretically and experimentally. Also, the possible mechanism for the enhancement of photocatalytic performance, the degradation pathway of MBT, photogenerated carrier transfer behaviors are also discussed in depth. This research provides a new strategy to control the thickness of CN to improve photocatalytic activity.