PtRu alloy nanoparticles supported on nanoporous gold as an efficient anode catalyst for direct methanol fuel cell

Abstract

An efficient and CO-tolerant anode catalyst for direct methanol fuel cell is fabricated by depositing PtRu alloy nanoparticles (∼3 nm) on nanoporous gold film (NPG-PtRu). Those catalysts with various Pt/Ru molar ratios are prepared by using linear scanning voltammetry and their electrocatalytic activities are measured for methanol oxidation reaction (MOR) and CO oxidation. Owing to the notably reduced CO adsorption energy, NPG-PtRu catalyst with Pt/Ru molar ratio of ∼2:1 exhibits close CO-tolerance but 3-fold enhanced MOR activity in contrast to commercial JM-PtRu/C, and thus is chosen as the anode in direct methanol fuel cell. The membrane electrode assembly with anode of NPG-PtRu (0.2 mgPt cm−2 and 0.3 mgAu cm−2) shows a maximum power density of 96 mW cm−2, about 6-fold enhancement of Pt efficiency than that of commercial PtRu/C (1 mgPt cm−2, 78 mW cm−2) under similar conditions.