Pt-Ru/polyaniline/carbon nanotube composites with three-layer tubular structure for efficient methanol oxidation

Abstract Developing anode catalyst with highly active and CO tolerance of direct methanol fuel cells is of prime importance. In this work, the polyaniline/carbon nanotube composites were fabricated via in situ electrochemical method. The Pt–Ru alloy nanoclusters were well-distributed on polyaniline/carbon nanotubes supporting materials by co-electrodeposition method. SEM, HRTEM and XPS were employed to investigate the surface features of composites. The results indicated that Pt-Ru/polyaniline/carbon nanotubes composites were formed three-layer tubular structure. The Pt9.8Ru1/polyaniline/carbon nanotubes catalyst displayed good performance along with the lower peak potential of forward-scanning methanol oxidation, longer-term stability and higher current density compared to Pt/C, Pt-Ru/carbon nanotube composites and other Pt-Ru/polyaniline/carbon nanotube composites. The current density of the Pt9.8Ru1/PANI/CNTs catalyst for methanol oxidation was 8.9 folds higher than that for Pt/C and 2.4 folds higher for Pt9.8Ru1/CNTs catalyst, which indicated that this catalyst had a high number of active sites and surface Ru sites could effectively facilitate the removal of COad. Our data showed that the prepared Pt-Ru/polyaniline/carbon nanotubes composites are potential candidate as bimetallic electro-catalysts for methanol oxidation reaction.