Gold modified TiO2/g-C3N4 for enhanced photocatalytic activities to evolved H2 fuel

Plasmonic Au/TiO2/g-C3N4 nanocomposites have been successfully prepared by simple hydrothermal method. It is demonstrated that the as-synthesized nanocomposites show significant co-catalyst-free photocatalytic activities for H-2 evolution under visible-light. The amount-optimized 1Au/4TiO(2)/g-C3N4 nanocomposite evolved 250 mu mol.g(-1)h(-1) H-2 at lambda > 400 light illumination. The improved photocatalytic activities for H-2 evolution is attributed to the greatly-enhanced photoexcited charge separation by electron transfer from Au surface plasmon (similar to 520 nm) and CN (470 nm > lambda > 400) to TiO2. Based on the surface photovoltage spectra, photoelectrochemical I-V curves, hydroxyl radical amounts related spectra, and photocurrent action spectra, it is suggested that the fabricated Au/TiO2/g-C3N4 nanocomposite provide a proper energy platform for the photocatalytic H-2 production. Moreover, TiO2 is much superior as compare to other wide-band gap metal oxides as energy platforms, like SnO2 and ZrO2. This work would provide a feasible strategy to synthesize an efficient plasmonic-assisted CN-based nanophotocatalyst for solar fuel production.

Automated summary

Au/TiO2/g-C3N4 nanocomposites prepared through a hydrothermal method exhibit significant photocatalytic activities for H-2 evolution under visible-light, with the optimized nanocomposite showing a high H-2 production rate. The enhanced photocatalytic activities are attributed to improved charge separation and energy platform for H-2 production, making TiO2 a superior material compared to other wide-band gap metal oxides for solar fuel production.