Activation of g-C3N4 by oxidative treatment for enhanced photocatalytic H2 evolution

Graphitic carbon nitride g-C3N4 has attracted a scientific interest as a visible light active non-metallic photo-catalyst for a H2 evolution. Recently, the techniques aimed at oxidizing g-C3N4 surface have been investigated in order to improve its photocatalytic properties. The present study is devoted to the modification of g-C3N4 via hydrothermal treatment in aqueous H2O2 solution. The treatment led to partial structural decomposition and functionalization of the g-C3N4 surface with-C=O and-COOH groups, thereby affecting the structural, textural, and electronic properties. The platinum deposited on the surface of the pretreated g-C3N4 was in a special configuration with metal particles surrounded by single atoms. The platinized g-C3N4 treated in H2O2 solution at 140 degrees C was shown to be active in H2 evolution from glucose aqueous solution with a reaction rate of 344 mu mol H2 center dot h-1 center dot(gcat)-1 (lambda max= 440 nm), while Pt/g-C3N4 without hydrothermal treatment demonstrated no activity. Moreover, the activity of platinized g-C3N4 after hydrothermal treatment was improved by a factor of 9.5 and 4.3 in ethanol and triethanolamine aqueous solutions, respectively. The study presents a novel simple avenue for the synthesis of g-C3N4-based photocatalyst for H2 generation from different substrates, including plant biomass components, thus expanding the scope of g-C3N4 applications.