Preparing copper doped carbon nitride from melamine templated crystalline copper chloride for Fenton-like catalysis

Heterogeneous catalysts prepared by doping metal ions in g-C₃N₄ have been demonstrated as a type of promising alternative to the traditional homogeneous Fenton catalysts. The metal–N_x active sites of metal doped g-C₃N₄ composites are responsible for their enhanced catalytic activity. However, it is very difficult to achieve high content of metal–N_x species through pyrolyzing the physical mixtures of metal salts and g-C₃N₄ or melamine. In this work, copper doped g-C₃N₄ composites were synthesized by pyrolyzing a melamine templated crystalline copper chloride [H₂mela]₂[CuCl₅]Cl. High content of Cu–N_x species were formed in these Cu-g-C₃N₄ composites. Compared with the catalysts prepared by pyrolyzing the physical mixtures of CuCl₂ and g-C₃N₄/mela, the Cu-g-C₃N₄ composites exhibited enhanced catalytic activities for the degradation of RhB, MO, and MB. This work suggests that crystalline metal chlorides contained melamine ligands could be employed as efficient precursors for synthesizing metal doped g-C₃N₄ composites with high content of metal-N_x species.