Photo-assistant electrocatalytic activity improvement towards oxygen evolution

Abstract As one of the most important reactions involved in water splitting, oxygen evolution reaction (OER) suffers from a slow kinetic. Herein, with a composite catalyst of Au/Co-FeOOH, it was shown that the photo-irradiation could greatly activate the catalytic performance for OER due to the plasmon effect of Au nanoparticles. With 532 nm of photo-irradiation, the overpotential at 10 mA cm−2 for OER decreased from 386 to 309 mV with the optimized composite. It is believed that the two factors, hot electron excitation promoting the formation of active species and the charge transfer modulating the electronic structure of active sites, are responsible for the enhancement of catalytic activity. These findings highlighted the possibility of activation of OER catalysis by photo-irradiation and would open up a new route for the design of advanced electrocatalysts.