Molten salt-lithium process induced controllable surface defects in titanium oxide for efficient photocatalysis

The efficiency of photoabsorption, photo-generated charge separation, and surface redox reaction determine the overall efficiency of photocatalysts. Therefore, exploring ways to simultaneously optimize the parameters is key to improving the photocatalytic performance. Herein, a novel low-temperature ternary molten salt-lithium reduction method is designed to create controllable oxygen vacancies (Ovs) as well as to manipulate the surface microstructure of the classic photocatalyst TiO2. The optimized TiO2 exhibits a 10-fold increase in the photocatalytic RhB breakdown rate and H2 generation quantity compared to pristine TiO2. The dual surface defects result in synergistic effects: i) Ovs lower band gap, enhance the charge separation efficiency as capture centers, and facilitate hydrogen adsorption; ii) the enlarged surface area enhances light-harvesting and provides more active sites. This research proposes a novel strategy for manipulating surface defects in a controlled manner and highlights the synergistic optimization of the thermodynamical and kinetical parameters to promote the photocatalytic performance.

Automated summary

This research proposed a novel low-temperature ternary molten salt-lithium reduction method to create controllable oxygen vacancies and manipulate the surface microstructure of TiO2 photocatalyst. The optimized TiO2 showed a significant improvement in the photocatalytic performance, with a 10-fold increase in the degradation rate of RhB and hydrogen generation compared to pristine TiO2. The synergetic effects of dual surface defects, including reduced band gap, enhanced charge separation efficiency, and increased surface area, played a crucial role in improving the overall efficiency of the photocatalyst.