Bimetallic PdAg nanoparticles for enhanced electrocatalysis of ethanol oxidation reaction

The exploration of bimetallic Pd-based catalysts has become a hot-spot for the application of high performance electrocatalysts with long term stability in fuels cell. In this work, alloyed PdxAg1 nanoparticles (NPs) (x = 8, 11, 14, 17, and 20) are synthesized via a solvothermal synthesis approach. The morphologies and compositions of alloyed PdAg NPs are characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The optimized Pd14Ag1 NPs exhibited excellent current activity in ethanol oxidation reaction (EOR) of 2430 mA mg−1 in an alkaline ethanol solution, 3.3 times higher than commercial Pd/C counterpart (727 mA mg−1), closely related to the change of electron structure and surface active sites. In addition, compared with other PdAg NPs and commercial Pd/C catalysts, Pd14Ag1 NPs performs better antitoxicity, lower reaction barrier, and better long-term stability. Experimental results show that higher catalytic temperature, higher pH values, and higher ethanol concentration should favor the oxidation of ethanol.