Coaddition of Phosphorus and Proton to Graphitic Carbon Nitride for Synergistically Enhanced Visible Light Photocatalytic Degradation and Hydrogen Evolution

Abstract

Graphitic carbon nitride (g-C3N4) has attracted enormous attention in photocatalysis owing to its special structure and properties. The insufficient light absorption and fast charge-carrier recombination limit its further photocatalytic application. Herein, we report a facile approach to fabrication of the g-C3N4 modified simultaneously with phosphorus and proton by directly heating the mixture of urea phosphate (UP) and urea in air. The incorporation of the phosphorus atoms in g-C3N4 can significantly decrease the band gap, leading to the enhanced light absorption efficiency. Furthermore, UP can also introduce the protons to the structure of g-C3N4 from protonation. The protons can inhibit the recombination of the charge carriers and improve their utilization. The synergistic effect of the phosphorus doping and protonation in g-C3N4 results in the superior visible-light photocatalytic performance for both degradation of Rhodamine B (RhB) and H2 evolution from water splitting. We believe that our findings have a broad applicability to design efficient and novel g-C3N4-based photocatalysts.