Facile one-pot pyrolysis preparation of SnO₂/g-C₃N₄ composites for improved photocatalytic H₂ production

BACKGROUND: Graphitic carbon nitride (g-C₃N₄) has attracted extensive attention as a typical photocatalyst. However, g-C₃N₄ still needs to be modified to obtain enhanced hydrogen production activity. RESULTS: Here, SnO₂/g-C₃N₄ composites were prepared by a facile one-pot pyrolysis method, and showed enhanced visible-light-driven photocatalytic H₂ production activities with the highest value of 241 μmol h⁻¹ g⁻¹, which was about four times that of pure polymeric g-C₃N₄. The facile one-pot pyrolysis method not only promoted effective coupling between g-C₃N₄ and SnO₂, but also adjusted the photocatalytic performance-related physicochemical properties of polymeric g-C₃N₄. The reduction of particle sizes of g-C₃N₄ promoted the migration of photogenerated carriers to the surface and the introduction of SnO₂ as electron transport material promoted the transfer of photogenerated charge carriers from g-C₃N₄ host photocatalyst to metallic Pt cocatalyst, synergistically restraining the recombination of photogenerated carriers. Moreover, the increased specific surface areas and pore volumes enriched the reactive sites and facilitated the mass transfer of reactants, thus accelerating the redox reactions. Furthermore, the enhanced light absorption promoted the generation of photogenerated carriers which was beneficial for photocatalytic reactions. CONCLUSIONS: This work provides an effective reference for the application of Sn species in the modification of photocatalysts, especially polymeric g-C₃N₄.