Low-Silver PdAg/C Nanoalloys with Enhanced Activity and Poisoning Resistance for Alkaline Glycerol Electrooxidation

In this work, bimetallic PdAg nanoparticles supported on oxidized Vulcan XC-72R carbon (O-Vulcan) were synthesized via a pulsed microwave-assisted polyol method and evaluated for the electrooxidation of glycerol in alkaline media. The PdAg catalysts exhibited a homogeneous nanoparticle dispersion (ca. 6 nm) and evident alloy formation, as confirmed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). X-ray photoelectron spectroscopy (XPS) analysis revealed a negative shift in the Pd 3d binding energy, indicating electronic charge transfer from Ag to Pd. Among the as-prepared materials, PdAg10/C delivered the highest electrocatalytic performance, achieving a peak mass activity of 3 973 mA mg -1 at 30 °C, which is 2.1 times higher than that of Pd/C, along with an onset potential shift of 90 mV, and improved tolerance to poisoning of 61.6% during cycling. The enhanced performance correlates with the increased electroactive surface area, the electronic modification of Pd evidenced by XPS, and alloy-induced lattice expansion observed by XRD, consistent with a synergistic electronic and bifunctional effect. Compared with previously reported PdAg systems, the present catalysts achieve superior activity using low Ag content and a rapid microwave-assisted synthesis route. These results demonstrate the potential of PdAg/C catalysts as efficient anodes for alkaline electrochemical energy conversion.