Rationally Designed Copper-Modified Polymeric Carbon Nitride as a Photocathode for Solar Water Splitting.

Polymeric carbon nitride has been considered an active photocathode for catalyzing H2 generation via water splitting. However, the application of the material in photoelectrochemical cells remains a challenge owing to the intrinsically sluggish kinetics of charge separation. Here, we developed a facile salt melt method for fabricating Cu-modified polymeric carbon nitride as an effective photocathode material for solar water splitting. Various characterization data confirm that Cu-modified polymeric carbon nitride contains both free CuCl derived from precursors and coordinated Cu species incorporated into the polymeric carbon nitride, which can generate type-II heterojunctions. This special heterojunction energy structure could contribute to significantly enhanced photocurrent density for hydrogen evolution. The proposed strategy for synthesizing of the Cu-modified polymeric carbon nitride can stimulate research into developing highly efficient visible-light active photocathodes.