Palladium nanoparticles/nanostructured carbon black composite on carbon–ceramic electrode as an electrocatalyst for formic acid fuel cells

Abstract

Palladium nanoparticles/nanostructured carbon black composite (PdNPs/NCB), supported on the carbon–ceramic electrode (CCE), has been prepared by a chemical reduction method using sodium borohydride as a reducing agent. The synthesized composite was characterized by scanning electron microscopy, high resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and electrochemical methods to delineate its surface morphology, nanostructure properties, composition, crystal phases and electrochemical properties. The obtained modified electrode, PdNPs/NCB/CCE, was used as an efficient electrocatalyst for the oxidation of formic acid. Electrochemical techniques including cyclic voltammetry and chronoamperometry were applied for electrocatalytic investigations and it was found that the PdNPs/NCB/CCE was catalytically more active than the Pd nanoparticles supported on the CCE without NCB (PdNPs/CCE). The effect of some experimental factors was studied and optimum conditions were suggested. The obtained results show that the PdNPs/NCB/CCE has satisfactory stability and reproducibility for electrooxidation of formic acid when stored in ambient conditions and improved electrocatalytic activity in continued cycling which make it more attractive for formic acid fuel cell applications.