High activity of Au monolayer doped by Pt atom on WC (0001) surface towards H2 dissociation and high tolerance of sulfur poisoning

Abstract

The Nickel/Yttria-stabilized zirconia (Ni/YSZ) Solid Oxide Fuel Cells (SOFCs) anode faces the sulfur-poisoning problem. The criteria of ideal sulfur tolerant anode materials are weak atomic sulfur adsorption, high catalytic activity toward H2 dissociation and low cost. It is found that H2 dissociation barriers on Au (111), Au monolayer on WC (0001) (AuML/WC), Au monolayer doped by Pt atom on WC (0001) (AuMLPt-d/WC) surface are decreasing from 0.98 to 0.1 eV. The ab initio atomistic thermodynamic data shows that at typical SOFC operating temperatures of 923–1073 K, for any pH2S/pH2, AuMLPt-d/WC can be sulfur free clean surface. Therefore, we proposed AuMLPt-d/WC as ideal sulfur tolerant anode materials.