Active role of buried ultrathin oxide layers in adsorption of O2 on Au films

Ultrathin oxide layers can exhibit special behavior by enabling the coupling of structural distortions and charge transfer beyond that allowed in the bulk. In this work, we show from first-principles calculations that ultrathin layers of titania, a prototypical oxide, are active in stabilizing adsorption of O2 on Au overlayers. The adsorbed O2 molecules induce charge redistribution in Au that penetrates to the Au-titania interface, which responds through structural distortions that lower the total energy of the system. We suggest that this effect may be of more general nature and useful in catalysis.