Synergistic collaboration of g-C3N4/SnO2 composites for enhanced visible-light photocatalytic activity

• g-C3N4/SnO2 composite was synthesized by simple method for the first time.
• The g-C3N4/SnO2 composite is a green material which was harmony with the environment.
• g-C3N4/SnO2 composite shows enlarged specific surface area than pure g-C3N4.
• Heterojunction between these two components of g-C3N4/SnO2 composite promotes the separation of photo-generated carriers.
• The g-C3N4/SnO2 composite shows enhanced photocatalytic activity.

A series of novel composites g-C3N4/SnO2 were first synthesized using a facile two-step process. Through systematic sample characterization, it is demonstrated that all composites consist of two components: g-C3N4 with a low specific surface area and SnO2 nanoparticles with a large specific surface area. Within the composites, component of SnO2 nanoparticles dispersed well onto the component g-C3N4 with a clear interface between each other. The interactions between both components are strong, as confirmed by variations in binding energies and lattice parameters. A synergistic collaboration is achieved for the composites, as contributed by surface adsorption of organics from π–π conjugation of component g-C3N4, improved separation efficiency of photo-generated carriers from interfacial interactions between both components, and increased surface area from component SnO2 nanoparticles. As a consequence, these composites exhibit a significantly enhanced photocatalytic activity towards MO degradation under visible light irradiation. The optimum photocatalytic performance is achieved at 47.5 wt% SnO2, showing a reaction kinetic constant of 0.0078, which is much higher than those of components g-C3N4 and SnO2. With the unique synergistic collaboration, the optimized composite with Pt additives is also successfully applied to high-efficiency production of hydrogen from water splitting under visible light irradiation.

Visible-light-driven g-C3N4/SnO2 composites show enhanced photocatalytic activity on MO degradation and hydrogen production from water splitting.Figure optionsDownload as PowerPoint slide