Glycerol Electrooxidation on Phosphorus-Doped Pt-αNi(OH)2/C Catalysts

This work investigates the electrooxidation of glycerol in an alkaline environment at non-doped and P-doped Pt-alpha Ni(OH)(2) nanoparticles supported on oxidized Vulcan XC-72R carbon. Pt-alpha Ni(OH), and PtP-alpha Ni(OH)(2) particles with sizes in the range of 3-5 nm were obtained via a one-step chemical reduction approach. The physicochemical characteristics of the as-prepared catalysts were studied by inductively coupled plasmaoptical emission spectrometry (ICP-OES), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and x-ray diffraction (XRD) techniques. It was determined that the incorporation of phosphorus lead to the formation of amorphous PtP-alpha Ni(OH)(2) deposits. TEM analysis showed that the incorporation of phosphorus into the bimetallic Pt-alpha Ni(OH)(2 )catalyst origins a remarkable reduction in the average size of the nanoparticles with a narrow size distribution. A substantial improvement in the electrocatalytic properties of the Pt-alpha Ni(OH)(2) system toward the oxidation of glycerol was observed through P doping. The P-doped electro-catalysts developed a mass current density of 60.3 mA mg(pt)(-)(1) at 765 mV vs. RHE, which is about 5 and 45 times higher than those of commercial PtRu/C (12.3 mA mg(pt)(-1)) and as-synthesized Pt-alpha Ni(OH)(2)/C (1.5 mA mg(pt)(-1)), respectively. The temperature-dependent experiments displayed that the apparent activation energy for the reaction is halved upon the addition of phosphorus.