Methanol oxidation DEMS study

Wang H, Baltruschat H. 2007. DEMS study on methanol oxidation at poly- and monocrystalline platinum electrodes The effect of anion, temperature, surface structure, Ru adatom, and potential. J Phys Chem C 111 7038-7048. 

Wang H, Loffler T, Baltmschat H. 2001a. Formation of intermediates during methanol oxidation A quantitative DEMS study. J Appl Electrochem 31 759-765. 

Wang H, Wingender Ch, Baltmschat H, Lopez M, Reetz MT. 2001b. Methanol oxidation on Pt, PtRu, and colloidal Pt electrocatalysts A DEMS study of product formation. J Electroanal Chem 509 163-169. 

Willsau J, Wolter O, Heitbaum J. 1985. On the nature of the adsorbate during methanol oxidation at platinum A DEMS study. J Electroanal Chem 185 163-170. 

To complete this DEMS study, the electro-oxidation of bulk methanol was also considered (Fig. 21). 

There still stands valid for platinum alloys the two metals that are able to promote methanol oxidation are ruthenium and tin. The case of ruthenium is interesting since it was also studied under UHV conditions [43,44]. The reaction of methanol on Pt/Ru alloys results in the production of carbon dioxide at lower potentials than on pure platinum. However, the presence of tin in Pt3Sn alloys only enhances methanol oxidation at low potentials, increasing carbon dioxide production (and diminishing carbon monoxide production) [45]. The addition of tin (II) ions to previously adsorbed methanol produces a fast oxidation process, demonstrated by DEMS experiments [46]. 

Wang H (2001) In Baltruschat H (ed) Co-Ad coverage and current efficiency of methanol oxidation studied by DEMS and potential step. DMFC Symposium, Meeting of the Electrochemical Society 2001, Washington, DC Narayanan SR (ed) The Electrochemical Society, Washington, DC... 

Abstract In this chapter, we present new insights in direct alcohol fuel cell-related anode electrocatalysis based on quantitative differential electrochemical mass spectrometry (DEMS) studies. First, we review the history and development of the DEMS technique, as well as the calibration method for quantification. We then discuss some contributions of quantitative DEMS to the study of the mechanism of methanol electrooxidation on Pt and PtRu model catalysts. We also discuss quantitative DEMS studies of the mechanism of dissociative adsorption and electrooxidation of ethanol and acetaldehyde at Pt, Pt3Sn, PtRu, and PtRh nanoparticle catalysts. Finally, the mechanism of dissociative adsorption and electrooxidation of ethylene glycol and its oxidative derivatives on carbon-supported Pt, Pt3Sn, and PtRu nanoparticle catalysts are discussed, based on quantitative DEMS results. 

Itmumerable mechanistic studies of alcohol oxidation on Pt-based electrocatalysts in acidic media have been published over the last few years. Methanol, " ethanol ° and ethylene glycol have been the most studied substrates and their oxidation paths on Pt or Pt alloys have been substantiated using a variety of in situ, extra situ and operando techniques as well as quantum mechanical calculations. The experimental techniques include reflection IR spectroscopy (IR), surface enhanced IR asbsorption spectroscopy (SEIRAS), " attemrated total reflection-IR absorption spectroscopy (ATR-IRAS), differential electrochemical mass spectroscopy (DEMS), single potential alteration IR spectroscopy... 

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