Surface-tailored PtPdCu ultrathin nanowires as advanced electrocatalysts for ethanol oxidation and oxygen reduction reaction in direct ethanol fuel cell

Abstract

The development of advanced electrocatalysts for efficient catalyzing ethanol oxidation reaction (EOR) and oxygen reduction reaction (ORR) is significant for direct ethanol fuel cells (DEFCs). However, in many previous studies, the major difficulties including lower utilization efficiency and weaker anti-CO-poison ability of Pt hamper the practical testing of such DEFCs. Herein, ternary Pt22Pd27Cu51 ultrathin (~5 nm) NWs are fabricated via a facile surfactant-free strategy. The surface and electronic structures of Pt22Pd27Cu51 NWs are further tailored via acid-etching treatment. The resulted PtPdCu NWs with an optimal atomic Pt/Pd/Cu ratio of 36:41:23 display excellent specific activities towards EOR (4.38 mA/cm2) and ORR (1.16 mA/cm2), which are 19.8- and 5.7-folds larger than that of Pt/C, respectively. A single-cell was fabricated using Pt36Pd41Cu23 NWs as electrocatalyst in both anode and cathode with Pt loading of 1.2 mgPt/cm2. The power density measured at 80 °C is 21.7 mW/cm2, which is ~3.9 folds enhancement relative to that fabricated by using Pt/C (2 mgPt/cm2). The enhanced catalytic performance of Pt36Pd41Cu23 NWs could be attributed to that synergistic effect between Pt, Pd and Cu enhances CO anti-poisoning ability and promotes the C–C bond cleavage. This work provides a promising strategy for developing efficient electrocatalysts for DEFCs.