Defect-mediated electron transfer in photocatalysts

Photocatalysis holds great potential in alleviating the growing energy crisis and environmental issues. Defect engineering has been demonstrated as an effective method to modulate the electronic structure of semiconductor photocatalysts for enhanced visible light absorption. However, the effect of defects on photocatalytic activity is still under debate because of the elusive charge transfer process mediated by defects. In this feature article, we summarize our recent progress in unraveling the defect-mediated electron transfer of the widely studied TiO2 and polymeric carbon nitride photocatalysts by combining ultrafast time-resolved spectroscopy and theoretical simulations. We find that the photogenerated electron transfer is greatly dependent on the type and concentration of defects. The location and occupation of defect states, and the dispersion degree of the energy band should be carefully tuned to maximize the advantages of defects for photocatalytic reactions.

Automated summary

This article summarizes the recent progress in unraveling defect-mediated electron transfer in TiO2 and polymeric carbon nitride photocatalysts through ultrafast time-resolved spectroscopy and theoretical simulations. The study reveals that the photogenerated electron transfer is significantly influenced by the type and concentration of defects, highlighting the importance of carefully tuning the defect states, occupation, and dispersion degree for maximizing the advantages of defects in photocatalytic reactions.