Electrocatalysis at palladium nanoparticles: Effect of the support nitrogen doping on the catalytic activation of carbon-halogen bond

Pd nanoparticles (NPs) were deposited electrochemically on three differently modified glassy carbon (GC) supports: pristine GC, nitrogen implanted GC and Ar implanted GC. The aim of such an approach is to discriminate whether the electrocatalytic activity of Pd NPs toward the activation of carbon halogen bond is preferentially driven by chemical or morphological defects. Modified GC electrodes were prepared by ion implantation whereas Pd was deposited according to a double-step potential deposition in a 1 mM PdSO4 +0.1 M H2SO4 solution. The electrodes were fully characterized by X-ray photoemission spectroscopy, which allowed the identification of several different N-based defects. Pd NPs morphology, dimension and distribution were investigated by scanning electron microscopy. The outcomes indicate that the electrodeposition of Pd NPs on nitrogen-implanted GC results in smaller catalyst particle sizes and higher particle dispersion with respect to pristine GC. The palladium nitrogen-implanted electrode was tested in the electrochemical reduction of benzyl chloride, showing that Pd NPs result in a much higher catalytic activity than bulk Pd and Pd NPs loaded on the pristine GC electrode. (C) 2013 Elsevier B.V. All rights reserved.