Photocatalysts based on g-C3N4-encapsulating carbon spheres with high visible light activity for photocatalytic hydrogen evolution

Graphitic carbon nitride-based nanocomposites hold great promise in photocatalysis. In this study, nanocomposites based on graphitic carbon nitride-encapsulating carbon spheres (CS/g-C3N4) were facilely fabricated through polymerization of melamine from the carbon spheres. The incorporation of carbon spheres in g-C3N4 leads to enlarged contact area and strengthened interaction between the two π-conjugated components. The CS/g-C3N4 composites exhibit large specific surface area, improved visible light utilization, more negative potential of conduction band, and enhanced separation of photo-generated charge carriers. The optimized CS/g-C3N4 composite displays a hydrogen evolution rate of 50.2 μmol h−1, which is almost 4.8 times of that over the pure g-C3N4. The structures and morphologies of the catalysts can be maintained after photocatalytic reaction. This approach may stimulate a new way to construct g-C3N4-based nanocomposites with other carbon materials.