Cu-template-dependent synthesis of PtCu nanotubes for oxygen reduction reactions

Abstract

The development of electrocatalysts with high activity and durability for oxygen reduction reaction (ORR) in acidic electrolyte environments remains a serious challenge for clean and efficient energy conversion. Synergistic effects between Pt and inexpensive metals, the d band center of Pt and catalyst morphology could adjust the adsorption and desorption of oxygen intermediates by the Pt. All the factors affect the catalytic performance of Pt-based nanocrystals. Here, we prepared Cu@PtCu3 NWs with an average diameter of 74.9 nm for Cu and about 10 nm PtCu3 layer. After etching, the Cu@PtCu3 nanowires is transformed into PtCu nanotube structure, due to the removal of copper from the surface and interior. PtCu NTs for ORR shows excellent activities and durability due to the integration of structural advantages and synergistic effects. Notably, the mass activity and specific activity of PtCu NTs (0.105 A mg−1Pt and 0.230 mA cm−2Pt) are 2.0 and 3.8 times higher than that of commercial Pt/C (0.053 A mg−1Pt and 0.06 mA cm−2Pt). The etching process to change the morphology of the catalyst and alter the electronic structure of the catalyst is expected to be useful for the design of future structured Pt-based alloy nanocatalysts.