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Abstract: This work reports improved electrode kinetics of ethanol oxidation on the conducting polymer composite matrix, poly-vinyl carbazole (PNVC) crossed linked with V2O5 and embedded with Pt-Pd nano crystallites. The metal incorporated polymer composite produces much higher current for ethanol electro-oxidation in alkaline medium compared to their carbon supported counterpart. The former also exhibits higher tolerance to CO-poisoning leading to a satisfactory level of ethanol conversion to the end products as estimated by chromatographic analysis. The structure and morphology of the catalysts surface were determined by SEM and XRD analysis. Various electrochemical techniques were employed to evaluate the kinetic parameters related to electro-oxidation of ethanol. Activation energy for the oxidation reaction is remarkably reduced, using the PNVC support, consistently throughout an extended potential region. [Copyright &y& Elsevier] more...

This paper involves a novel approach for synthesizing single Pt and binary catalysts, PtRu of different compositions by pulse electrodepostion technique using Nafion as template during fabrication of the anode, whereby maximum utilization of nanoparticle is possible. In this investigation, Nafion templated metal nanoparticles were characterized by X-ray Diffraction Analysis (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) techniques. The surface morphology and topographical analysis of the templated catalysts reveal the existence of fairly well distributed nano size particles imparting high roughness area to the catalyst matrix. By use of Nafion template the best catalyst formulation to promote the ethanol oxidation was identified to be one with 23 at.% Ru in the binary matrix. Kinetic investigations on ethanol electro-oxidation were conducted through various electrochemical techniques like cyclic voltammetry (CV), polarization, chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). • Pt and Pt-Ru nano-catalysts electrochemically synthesized using Nafion template. • Pt 77 Ru 23 found best catalyst formulation promoting ethanol oxidation in fuel cell. • Nafion template enable efficient catalyst utilization and significant cost benefits. • Low Pt loading in binary matrix achieved without compromising current output. [ABSTRACT FROM AUTHOR] more...

Abstract: In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts (Pt/C, PtPd/C, PtAu/C, PtPdAu/C) have been synthesized under borohydride reduction scheme and applied for the study of the electro-oxidation of ethanol in alkaline media at room temperature. The surface morphology of the catalysts was determined by XRD (X-ray diffraction) & TEM (transmission electron microscopy) analysis. XRD patterns reveal that all the catalysts have disordered face center cubic lattice structures. Low resolution TEM images reveal uniform dispersion of metal nano particles on carbon support having an average size of 3–4.5 nm. HRTEM is also carried out for the determination of the distance between the lattice planes. Different textural properties including external surface area, pore volume and widths of the catalyst matrix were calculated by applying the BET equation to the adsorption isotherms. During electrolysis substantial increase in anodic peak current was observed for ethanol oxidations when the second and third metal component was introduced into the Pt matrix as in case of PtPdAu/C catalysts. The charge transfer resistance (R ct) for ethanol oxidation was substantially reduced from 87.9 Ω on Pt/C to 7.74 Ω on PtPdAu/C demonstrating the superior electrode kinetics behavior of the latter over the other catalysts studied. Thus Au and Pd incorporation into the Pt matrix not only increases the catalytic efficiency of the alloyed catalyst but at the same time effectively reduces the Pt content in the ternary system. [Copyright &y& Elsevier] more...