Graphene and Spherical CeO₂-ZrO₂ Support Pt Nanoparticles as Anode Catalysts for Direct Methanol Fuel Cells

Abstract

Spherical CeO2 and CeO2-ZrO2 solid solutions are prepared using a hydrothermal method, Pt/CeO2-ZrO2/GO and Pt-CeO2/GO catalysts are prepared using graphene as a carrier, and the effects of the addition of a CeO2-ZrO2 solid solution on the electrocatalytic activity, stability and anti-CO poisoning performance of methanol fuel cell anodes are investigated. The catalyst samples are characterized via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the electrochemical properties of the catalysts are investigated using an electrochemical workstation (IVIUM). The results show that Pt/CeO2-ZrO2/GO has a higher electrocatalytic activity and stability against CO oxidation than Pt-CeO2/GO, Pt/GO and commercial Pt/C catalysts, which is attributed to ZrO2. When Zr4+ is added into the CeO2 lattice, the activity of oxygen in the CeO2 lattice, the oxygen mobility and the oxygen vacancies are increased, the oxygen storage capacity is improved, and the intermediate product of CO is more easily oxidized. This finding indicates that Pt/CeO2-ZrO2/GO is a methanol oxidation anode catalyst with a good catalytic activity, stability and resistance to CO poisoning.