Glycerol electrooxidation on Pd, Pt and Au nanoparticles supported on carbon ceramic electrode in alkaline media

In the present study, electrooxidation of glycerol was investigated on Au, Pd and Pt nanoparticles modified carbon ceramic electrode (CCE) by using different electrochemical techniques such as: Cyclic voltammetry (CV), Chronoamperometry (CA), Chronopotentiometry (CP) and Electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were also employed to physicochemical survey of the electrocatalysts. The kinetic parameters of glycerol oxidation, i.e. Tafel slope and activation energy (Ea), were determined on the modified electrodes. The Tafel slopes of 166 mV dec−1 on Pt|CCE, 177 mV dec−1 on Au|CCE and 136 mV dec−1 on Pd|CCE were obtained. The lowest Ea value of 11.2 kJ mol−1 was calculated on Au|CCE. In continuation, the reaction orders with respect to the glycerol and NaOH concentrations on Pd|CCE were found to be 0.27 and 0.87, respectively. The CV, CP and CA results showed remarkable electrocatalytic activity and good poisoning tolerance of Au|CCE for glycerol oxidation.

► Au|CC & Pd|CC compared to Pt|CC have good poisoning tolerance for gly. oxidation.
► Au|CC has remarkable electrocatalytic activity for gly. oxidation.
► Lowest activation energy for gly. oxidation was obtained on Au|CC.
► Lowest & highest onset potential for gly. oxidation were obtained on Pt|CC & Au|CC.
► Gly. oxidation on Pd|CC has higher kinetics compared to two other electrodes.