PdPb bimetallic nanowires as electrocatalysts for enhanced ethanol electrooxidation

Abstract

Less-expensive but efficient electrocatalysts are essential to accelerate the commercialization of fuel cells. Herein, ultrathin PdPb nanowires (PdPb NWs) with a diameter of around 3.5 nm were prepared by using a one-step hydrothermal method. The introduction of Pb in Pd-based bimetallic nanostructures produced high differences in the morphology from Pd nanoparticles (NPs) to various PdPb NWs. All the as-prepared PdPb NWs exhibited better electrocatalytic activity and durability than Pd NPs due to the synergistic effect. Especially, Pd65Pb35 possessed the highest current density of about 3460 mA mgPd−1 for the ethanol electrooxidation which was around 6.3 times higher than commercial Pd/C. The high-performance of Pd65Pb35 is attributed to the defect-rich and stable nanowire structure with optimized surface atomic arrangement, as evidenced by high resolution transmission electron microscopy measurements and long-time treatment in an acidic media. The differences in the morphologies and electrocatalytic activities of PdPb NWs with varied Pb contents have also been discussed and analyzed.