Carbon supported palladium hollow nanospheres as anode catalysts for direct borohydride-hydrogen peroxide fuel cells

摘要

Carbon supported Pd hollow nanospheres (HN-Pd/C) are prepared by employing cobalt nanoparticles as sacrificial templates at room temperature in aqueous solution, and used as the anode electrocatalyst for direct borohydride-hydrogen peroxide fuel cell (DBHFC). The physical and electrochemical properties of the as-prepared nanospherical electrocatalysts are investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), linear sweep voltammetry (LSV), chronoamperometry (CA), chronopotentiometry (CP) and fuel cell test. The results show that the Pd nanospheres supported on the carbon are coreless and composed of a series of Pd nanoparticles with the average crystallite size of about 3.8 nm. Besides, the HN-Pd/C exhibits distinctly higher electrocatalytic activity for BH_4~(-) electrooxidation than the carbon supported Pd solid nanoparticles (SN-Pd/C), and the DBHFC using HN-Pd/C as anode electrocatalyst shows as high as 48.4mWcm~2 power densities at a discharge current density of 54.8 mAcm~2. Therefore, the HN-Pd/C catalyst can apparently improve the catalytic activity of BH_4~(-) electrooxidation and imply a promising application in the DBHFC.