Carbon hollow spheres as cocatalyst of Cu-doped TiO2 nanoparticles for improved photocatalytic H2 generation

The reasonable employment of cocatalyst in photocatalysis can effectively promote the photocatalytic H-2 production activity. In this study, carbon hollow spheres (C), as a good conductive nonmetallic material, have been utilized as a novel cocatalyst and a matrix for loading the Cu-doped-TiO2 nanoparticles by a successive hydrothermal method and metal molten salt method. The Cu-doped-TiO2 nanoparticles were tightly anchored on the surface of carbon hollow sphere to form a zero-dimensional/three dimensional (0D/3D) Cu-doped-TiO2/C heterojunction. The optimal Cu-doped-TiO2/C heterojunction demonstrated greatly enhanced photocatalytic H-2 generation activity (14.4 mmol.g(-1). h(-1)) compared with TiO2 (0.33 mmol.g(-1).h(-1)) and TiO2/C (0.7 mmol.g(-1).h(-1)). The performance improvement was mainly due to the synergistic effect of carbon hollow sphere cocatalyst and Cu-doping, the Cu-doping in TiO2 nanoparticles can minimize charge recombination and enhance the available photoex-cited electrons, while the 3D carbon hollow spheres can act as electron traps to accelerate the charge separation and offer abundant active sites for solar water splitting reaction.

Automated summary

This study successfully improved the photocatalytic H-2 production activity by loading Cu-doped TiO2 nanoparticles on carbon hollow spheres as a cocatalyst. The Cu doping minimized charge recombination and enhanced the available photoexcited electrons, while the carbon hollow spheres accelerated charge separation and provided abundant active sites.