Hydroxyapatite wrapped multiwalled carbon nanotubes composite, a highly efficient template for palladium loading for electrooxidation of alcohols

Abstract

A new electrocatalyst is introduced by loading palladium nanoparticles on the unique structured composite of hydroxyapatite and multiwalled carbon nanotubes. The structure and morphology of the designed electrocatalyst are characterized by X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The efficiency of the resulted nanostructure is explored toward the electrooxidation of some common alcohols in alkaline media. The electrooxidation of ethylene glycol (EG) is explored more extensively which provides a large peak current density (more than 1810 mA mg−1Pd). Surprisingly, the efficiency of oxidation is maintained even for relatively high concentrations of EG. In terms of the current density and the onset potential, significant improvements are observed for the proposed structure versus hydroxyapatite free catalyst. The high efficiency of the proposed electrocatalyst is explained via the presence of hydroxyl rich surface of hydroxyapatite which causes a more effective oxidation of alcohols over the loaded Pd nanoparticles.