Chlorine‐Modified Soluble Melem‐Based Graphitic Carbon Nitrite: Facile Synthesis, Catalytic Property and Ultrafast 2D IR Spectroscopic Characterization

On the basis of thermal etching bulk graphitic carbon nitride (g‐C 3 N 4 ), a mild hydrochloric acid treatment method was used in this work to produce g‐C 3 N 4 nano‐sheets (CNNS) and further carbon nitride with chloride‐modification (CNCl). The latter has thinner layer and smaller particle size and exhibit greatly improved dispersibility and solubility in water, DMSO and other polar solvents. A typical photocatalytic reaction in solution driven by CNCl shows a significantly improved photocatalytic performance over bulk g‐C 3 N 4 and CNNS. Steady‐state analytical tools including SEM, mass, UV‐Vis, and IR spectroscopies, and time‐resolved two‐dimensional infrared (2D IR) vibrational spectroscopy, were used together in this work. Better solubility, more flexible structure, smaller size, easier generation of free radicals and lower recombination rate of electron‐hole pair, are believed to be reasons for the superior photocatalytic performance of CNCl.