Pd coated one-dimensional Ag nanostructures: Controllable architecture and their electrocatalytic performance for ethanol oxidation in alkaline media.

One-dimensional (1D) metal-coated Pd structures are efficient catalysts for the ethanol electro-oxidation and promising strategy for minimizing the Pd-loading toward commercialization of direct ethanol fuel cells (DEFCs). Herein, the decorated and core-shell architectures of a novel Pd coating on Ag nanowires (PdAg-NWs) are controllable by a two-step polyol method based on the galvanic replacement reaction. The integration of uniform shell with a low Pd concentration and partial hollow structure onto 1D PdAg-NWs exhibits the highest efficiency for ethanol oxidation reaction (EOR) in alkaline solution. In comparison with Pd nanoparticles (PdNPs/C), the PdAgNWs/C performes 11 times superior EOR activity, and the onset potential shifts 80 mV negatively. The presence of Ag in PdAg-NWs enhances the absorption capacity of ethanol molecules and hydroxyl ions on the active sites, and improves the catalyst tolerance to CO-like intermediates, making them a potential anodic catalyst for DEFCs. Image 1 • Novel PdAg core-shell nanowires with a low Pd-loading were synthesized. • Controllable configuration of Pd layer by temperature and PVP concentration. • Adjustable particle size of Pd by reaction time and Pd/Ag molar ratio. • Efficient bifunctional electrocatalyst for direct ethanol fuel cells in alkaline media. [ABSTRACT FROM AUTHOR]