Carbon Nitride Functionalized with Sb Resulting in High Photocatalytic Activity

Composites based on Sb clusters anchored on graphitic carbon nitride (g-C3N4) are prepared via a hierarchical sealed-tube calcination method. In the first stage, thermal treatment brings the density and crystallinity of g-C3N4 to substantially increase, resulting in 4.5 times higher photocatalytic efficiency toward water splitting for hydrogen generation. After further calcination under sealed-tube conditions, Sb species are successfully anchored on the edge of the pores within the g-C3N4 matrix in the form of atomic clusters. Photocatalytic hydrogen generation from the resulting Sb@C3N4 is further enhanced 14.4 times compared with the pristine g-C3N4. Such an improvement can be ascribed to the tuning of the electronic structure in Sb@C3N4 and hastened charge transfer.