Green dual-template synthesis of AgPd core-shell nanoparticles with enhanced electrocatalytic activity.

A key challenge in developing an ethanol oxidation reaction is nontoxic fabrication of highly active stable and low-cost catalysts. Here we design a green synthetic strategy of AgPd bimetallic nanosphere by a dual-template cascade method. The Pd nanoshell is firstly prepared using Vapreotide acetate as a primary template, and then the Ag nanoshell acts as a secondary template for the distribution of AgPd alloy nanoparticles. The AgPd nanoparticles have core-shell structures and various sizes, and their shell thicknesses are tuned by controlling the amount of PdCl. The six different samples are prepared, named AgPd-1, AgPd-2, AgPd-3, AgPd-4, AgPd-5, and AgPd-6, respectively. The mass current density of AgPd-5, is higher 3.87 times that of commercial Pd/C, and exhibits the best ethanol oxidation reaction activity and long-term stability. The main reasons are that the AgPd-5 possessed excellent specific surface area due to their rough structure, and Ag can remove more CO-like species. This is the first time a Vapreotide acetate/Ag-template method has been used to synthesize a AgPd core-shell structure, which would have broad application prospects for direct ethanol fuel cells.