Enhanced catalytic properties of Pt-based electrode by doped Cu and Ce

Abstract

Novel PtCuCeOx composite membrane electrode materials were fabricated on the surface of graphite fibrous cloth by ion beam sputtering (IBS). The cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to analyze the influence of doped Cu and Ce on the membrane electrocatalysis performance in a tri-electrode system. The phase composition, surface structure, interfacial structure and catalytic performance of PtCuCeOx membrane were studied by x-ray diffraction (XRD) and high resolution transmission electron microscope (HR-TEM&STEM). The results indicate that surface particles of membrane electrode are made up of PtCu alloy grains and a few CeOx grains, and the interface structure of oxide metal is formed between them. The crystal plane spacing between PtCu alloy grain is reduced by about 1.11% after the corrosion, which helps increase the electron density on Pt atom. As a result, the catalysis capability of PtCu alloy is enhanced. When the content of Ce is less than or equal to 0.28 wt.%, CeOx exists in the form of amorphous. It is exciting to demonstrate that the existence of CeOx enhances the dispersion of PtCuCeOx catalyst particles. The experimental results reveal that the synthesized material possesses the best electrochemical activity surface area (ESA) and exchange current density (i0). Compared to pure Pt catalyst, this PtCuCeOx catalyst contains much less Pt content (only 42% of Pt catalyst). However, the electrochemical performance is enhanced by 71.8% compared with pure Pt.