Electrocatalytic Promotion of Pt Nanoparticles by Incorporation of Ni(OH)2 for Glycerol Electro-Oxidation: Analysis of Activity and Reaction Pathway

In this work, the effect of Pt-Ni(OH)(2) nanoparticles on the activity and reaction pathway of glycerol oxidation was studied. For this purpose, small Pt (4 +/- 0.2 nm) and Pt-Ni(OH)(2) nanoparticles (4.7 +/- 0.4 nm) supported on Vulcan carbon were synthesized. Ni(OH)(2) were found in the vicinity of Pt modifying the lattice parameter, inter-planar distance and binding energy of Pt. Electrochemical evaluation indicated that Pt-Ni(OH)(2)/C had better electrocatalytic activity than Pt/C offering a higher current density (almost 45 mA mg(-1)), and lower onset (-0.3 V) and oxidation peak potentials (0.04 V). The improved activity was associated to the OH groups found in the vicinity of Pt active sites, facilitating the charge transfer due to a bifunctional mechanism. The in situ evaluation confirmed that the incorporation of Ni(OH)(2) led to higher electron transfer due to short-chain byproducts such as glycolate, mesoxalate and formate, which were found at the oxidation peak potential.