Effect of deposition sequence of platinum and ruthenium particles into nanofibrous network of polyaniline–poly(styrene sulfonic acid) on electrocatalytic oxidation of methanol

This study reports on the preparation of Pt- and Ru-based electrocatalysts through electrodeposition of Pt and Ru particles into the nanofibrous network of polyaniline (PANI)–poly(styrene sulfonic acid) (PSS). The sequence of electrodeposition of Pt and Ru particles was changed and the electrocatalysts, PANI–PSS–Pt–Ru and PANI–PSS–Ru–Pt, were obtained. Scanning electron microscopy (SEM), X-ray photoelectron microscopy (XPS), and cyclic voltammetry (CV) were employed to investigate the morphology, structural and electrochemical properties of the electrocatalysts, PANI–PSS–Pt–Ru and PANI–PSS–Ru–Pt. The distribution of Pt and Ru particles into PANI–PSS matrix was analyzed by the Auger depth profiles. The electrochemical behavior PANI–PSS–Pt–Ru and PANI–PSS–Ru –Pt and the electrocatalytic behavior toward oxidation of methanol were evaluated by cyclic voltammetry. PANI–PSS–Ru–Pt exhibited a superior electrocatalytic performance for methanol oxidation as compared to PANI–PSS–Pt–Ru.