Ultrafine SnPd Nanoalloys Promise High-Efficiency Electrocatalysis for Ethanol Oxidation and Oxygen Reduction

The catalytic activity and stability of palladium (Pd)-based electrocatalysts for ethanol oxidation reaction (EOR) and oxygen reduction reaction (ORR) can be improved by optimizing their composition and structure. Alloying tin (Sn) into Pd can induce electronic and synergistic effects, which weaken the adsorption of intermediate species (e.g., O and OH in ORR and CO in EOR) on Pd sites and even promote their further transformation. However, the SnPd alloys often suffer from complicated synthesis, large particle size, and inhomogeneity. In this context, we report the synthesis of SnPd nanoalloys with an ultrafine size of ca. 3.8 nm using a simple one-pot approach and their superior catalytic performance for EOR and ORR. Specifically, the SnPd alloy nanoparticles with an optimized Sn/Pd ratio of 18/82 show the mass and specific activity of 3.8 A mg –1 and 5.72 mA cm –2, respectively, for EOR, while excellent performance for ORR with a half-wave potential of 0.92 V and specific activity of 3.46 mA cm –2 at 0.9 V, both of which are much higher than those of their commercial Pd/C and Pt/C counterparts.