Laser-Accelerated Mass Transport in Oxygen Reduction Via a Graphene-Supported Silver-Iron Oxide Heterojunction.

ABSTRACT

Mass-transport acceleration is essential toward enhanced electrocatalytic performance yet rarely recognized under irradiation, because light is usually reported to improve charge transfer. We studied laser-enhanced mass transport through the heterojunction between Ag and semiconductor Fe2O3 situated on graphene for oxygen reduction reaction. Because of the decreased mass-transport resistance by 59% under 405 nm laser irradiation, the current density can be enhanced by 180%, which is also supported by a theoretical calculation. This laser-enhanced mass transport was attributed to local photothermal heating and the near-field local enhancement. Easier desorption of OH- species occurring between the Fe and Ag centers under the laser accelerates the mass-transport centers.