From bimetallic PdCu nanowires to ternary PdCu-SnO₂ nanowires: Interface control for efficient ethanol electrooxidation

At present, although a large number of palladium-based nanowire electrocatalysts have been prepared, there are few reports on nanowires containing rich metal oxides. Herein, porous PdCu alloy nanowires and PdCu-SnO₂ nanowires were prepared by using a galvanic displacement synthesis method. Due to their one-dimensional structure, rough surfaces with non-homogeneous edges, electronic effect, and the advanced PdCu/SnO₂ interface of the as-synthesized PdCu-SnO₂ nanowire catalysts, they exhibited a mass activity of 7770.0 mA mg^-1 towards ethanol oxidation, which was 7.6-fold higher than that of Pd/C catalysts (1025.0 mA mg^-1). In addition, they behaved strong durability upon chronoamperometry and continuous cyclic voltammetry tests. The electrochemical measurements demonstrated that SnO₂ was introduced into the PdCu/SnO₂ interface, which promoted the oxidation of ethanol at a lower potential and accelerated the oxidation of Pd-CO_ads via SnO₂-OH_ads to regenerate the active sites. This research highlights the significance of introducing metal oxides into the nanostructure interface, and the performance of Pd-containing catalysts towards ethanol oxidation reaction was greatly improved.