Selective knockout of gold active sites

It has long been known that defects on a gold surface play an important role in electrocatalysis, but the precise mechanism has always been unclear. This work indicates that the defect sites provide partially filled d-orbitals that stabilize freeradical intermediates. Strong evidence for this hypothesis is that the sites can be selectively knocked out by treatment with OH• radicals generated by Fenton's reagent. The knockout effect is demonstrated using oxygen reduction, hydrogen reduction, and the redox electrochemistry of hydroquinone