Ramulifho, TendamudzimuOzoemena, Kenneth I.Modibedi, Remegia M.Jafta, Charl JeremyMathe, Mkhulu K.2012-09-042012-09-042012-01Tendamudzimu Ramulifho, Kenneth I. Ozoemena, Remegia M. Modibedi, Charl J. Jafta & Mkhulu K. Mathe,Fast microwave-assisted solvothermal synthesis of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated MWCNTs : Pd-based bimetallic catalysts for ethanol oxidation in alkaline medium, Electrochimica Acta, vol. 59, pp. 310-320 (2012), doi: 10.1016/j.electacta.2011.10.071.0013-4686 (print)1873-3859 (online)10.1016/j.electacta.2011.10.071http://hdl.handle.net/2263/19700The preparation of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated multi-walled carbon nanotubes (SF-MWCNTs) using a very rapid microwave-assisted solvothermal strategy has been described. Electrocatalytic behaviour of the SF-MWCNT-Pd and its ‘mixed’ bimetallic electrocatalysts (i.e., SF-MWCNT-PdSnmix and SF-MWCNT-PdNimix) towards ethanol oxidation in alkaline medium was investigated. The result shows that the mixed Pd-based catalysts (obtained by simple ultrasonic-mixing of the individual MWCNT-metal nanocomposites) gave better electrocatalytic activity than their alloy nanoparticles (obtained by co-reduction of metal salts) or Pd alone. The SF-MWCNT platform gave better electrocatalytic performance compared to the unsulfonated and commercial Vulcan carbons. Detailed electrochemical studies (involving cyclic voltammetry, chronoamperometry, chronopotentiometry, and impedance spectroscopy) prove that the electrocatalytic oxidation of ethanol at the SF-MWCNT-PdNimix platform is more stable, occurs at lower potential, gives lower Tafel slopes, with faster charge-transfer kinetics compared to its SF-MWCNT-PdSnmix counterpart. Also, result revealed that SF-MWCNT-PdNimix is more tolerant to CO poisoning than the SF-MWCNT-PdSnmix. The results provide some important insights into the electrochemical response of microwave-synthesised Pd-based bimetallic catalysts for potential application in direct ethanol alkaline fuel cell technology.en© 2011 Elsevier. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Electrochimica Acta. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Electrochimica Acta, vol 59, January 2012, doi: 10.1016/j.electacta.2011.10.071.Microwave synthesisEthanol oxidationSulfonated carbon nanotubesPd-M nanoparticle catalystsVoltammetryFast microwave-assisted solvothermal synthesis of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated MWCNTs : Pd-based bimetallic catalysts for ethanol oxidation in alkaline mediumPostprint Article