Cobalt clusters on g-C3N4 nanosheets for enhanced H2/H2O2 generation and NO removal

Abstract

A one-step thermal polymerization method was developed to create homogeneous metallic cobalt (Co) clusters on graphitic carbon nitride (g-C3N4) nanosheets. The size (less than 3 nm) and distribution of Co clusters were controlled by a subsequent acid treatment. Because of the nanofluidic channels, efficient charge transfer, and enhanced light harvesting ability, optimized Co/g-C3N4 nanoarchitectonics by acid treatment revealed excellent photocatalytic activities. The visible-light photocatalytic H2 generation, H2O2 evolution and NO removal rate of the nanoarchitectonics were 82, 4, and 2 times of those of g-C3N4 nanosheets, respectively, suggesting that integrating transition metal clusters on g-C3N4 nanosheets is a novel strategy for NO removal and water splitting. Interestingly, Co/g-C3N4 nanoarchitectonics were further heat-treated at high temperature to create Co clusters decorated N-doped carbon nanosheets, in which ideal performance in hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction in alkaline solution were observed. This result supplied an efficient route to construct non-noble metal multifunctional catalysts.