Pd/C catalysts synthesized by microwave assisted polyol method for methanol electro-oxidation

Pd/C (20 wt%) catalysts are synthesized using microwave-assisted polyol method and employed for methanol electro-oxidation. A narrow size distribution and uniformly dispersted Pd nanoparticles were achieved by adjusting the solution pH, addition of stabilizer KBr, microwave heating time and solvents. The structure, morphology and electrocatalytic activities of the catalysts are characterized with XRD, TEM and cyclic voltammetry(CV). The results show that the optimum addition of KBr (0.12 M) and NaOH (0.05 M) are respectively 4 mL and 5 mL, the proper heating time is 2 min. Solvents were found to be key factor for influence the performance of catalyst. The sample prepared in 10 vol % ethylene glycol and 90 vol % glycerol mixture under the optimal condition shows the best catalytic activity with its anodic peak current density reaching to 785 A/g Pd in deoxygenated 0.1 M KOH + 1 M CH₃OH mixed solution.