The Point of Zero Charge of Oxide Surfaces:An Intensive Property to Separate Electronic from Geometric Factors

摘要

Electrocatalytic activity depends on electronic as well as geometric factors.Activity is usually assessed,on a relative scale,by measuring the current at a constant potential.However,current is an extensive quantity which includes geometric effects.If the latter are not allowed for,understanding of the true factors on which electrocatalysis is based may be hampered [1].Electrocatalytic reactions occurring at oxide electrodes are usually accompanied by exchange of protons with the solution [2].On the other hand,the surface of oxides in aqueous solution is subject to acid-base dissociation of the surface OH groups formed by chemical interaction of the Lewie acid sites (surface metal ions)with water molecules.