Structural Effects and Electrooxidation Activity of a Two-Dimensional Multilayer PtRu/PtNd Alloy Nanostructure Thin Film

Abstract

The two-dimensional multilayer PtRu/PtNd alloy nanostructure thin film used for anode electrodes of micro-direct methanol fuel cells (DMFCs) was fabricated by multi-target ion beam sputtering (IBS). The surface chemical state, structure, surface layer structure, and morphology of the PtRu/PtNd thin-film were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), grazing incidence X-ray diffraction (GIXD), and atomic force microscope (AFM). Electrochemical properties were examined by CO-stripping voltammetry, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and chronoamperometry (CA). The structure and surface chemical state of the PtRu/PtNd thin film were found to have changed due to a strong interaction between Pt+, Ru+ and Pt+, Nd+ during the ion beam alternate sputtering deposition process. Abnormal peak widths in the XRD spectra as well as electron transfer between Pt and Nd have also been observed. The PtRu/PtNd thin-film is shown to have a special multiphase structure and electronic structure. The electrochemical activity-specific surface area of PtRu/PtNd thin-film was 115.00 m2·g-1, and therefor PtRu/PtNd thin-film catalysts exhibited higher catalytic activity for methanol electrooxidation in an acidic environment.