Electrocatalytic properties of Pt thin film deposited on different supports for methanol oxidation reaction: Influence of controlled heat treatment

Abstract

It is known that surface structure is one of the critical issues affecting the activities of electrocatalysts. Heat treatment is an efficient approach to induce the rearrangement of surface atoms and thus to tailor their catalytic properties. The surface characteristics of electrochemically deposited Pt thin films at different substrates, as well as the effect of thermal annealing, were probed for electrooxidation of CO and methanol. Our results show that heat treatment in the reductive atmosphere (95% Ar+5% H2) at 300 oC can substantially affect the degree of surface atom rearrangement and thus induce long-range order creating domains with large fractions of (111) and (100) sites without the use of an epitaxial template, translating into significant influence on their catalytic properties. Since the catalytic reactions take place at the surfaces, our work demonstrates an easy-to-implement way to control the atomic orientations in order to understand the relationship between structure and catalytic properties of catalyst for methanol oxidation and proposes a method to design advanced electrocatalysts.