Three-Dimensional Plasmonic Photoanodes Based on Au-Embedded TiO2 Structures for Enhanced Visible-Light Water Splitting

Plasmon-assisted visible light photocatalysis presents a possible solution for direct solar-to-fuel production. Here we investigate the plasmon-enhanced photocatalytic water splitting using different TiO2/Au electrode structures. Experimental data demonstrates that the Au embedded in TiO2 (Au-in-TiO2) electrode greatly outperforms the Au sitting on TiO2 (Au-on-TiO2) electrode. Numerical simulation shows that the local electric field is very intense in the semiconductor near Au nanoparticles, which causes the enhancement of electron–hole pair generation. A 3D Au-embedded TiO2 structure is thus proposed to further improve the light absorption and photocatalytic performance.