Ab initio study of the electrochemical H2SO4/Pt(111) interface

Abstract

The co-adsorption of H₃O⁺ and/or H₂O on SO₄²⁻/Pt(111) has been studied on the basis of DFT calculations. Several combinations of co-adsorbates have been considered in order to determine the most stable configuration. We find an adlayer of H₃O⁺ coadsorbed with SO₄²⁻/Pt(111) having either none or one additional H₂O molecule. When including the effects of an external electrode potential the nature of the adlayer is modified. This is also reflected in the behavior of the electrostatic potential normal to the surface, which should be directly comparable to future distance tunneling spectroscopy measurements.