Methanol intermediate

Different experimental approaches were applied in the past [6, 45] and in recent years [23, 46] to study the nature of the organic residue. But the results or their interpretation have been contradictory. Even at present, the application of modem analytical techniques and optimized electrochemical instruments have led to different results and all three particles given above, namely HCO, COH and CO, have been recently discussed as possible methanol intermediates [14,15,23,46,47]. We shall present here the results of recent investigations on the electrochemical oxidation of methanol by application of electrochemical thermal desorption mass spectroscopy (ECTDMS) on-line mass spectroscopy, and Fourier Transform IR-reflection-absorption spectroscopy (SNIFTIRS). 

It is likely that the intermediate [ Rh(CsMe5) 2(OMe)jp, formed by reaction of the (/r-OH)3 derivative with methanol, is protonated by a Hpz ligand to form a methanol intermediate, which immediately reacts with the pz groups to give Complexes 160-165. 

ADSORPTION ENERGIES OF METHANOL INTERMEDIATE FRAGMENTS AND THE ENERGETICS OF METHANOL AND H2O DEHYDROGENATION... 

Pt(lll) was chosen again as the stxrface for adsorption of methanol intermediate species. The Pt(l 11) surface was simulated by a two-layer (Pt3)(Pt7) cluster model, containing seven platinum atoms in the first layer and three in the second. In the case of mixed Pt-M metal (M = Ru, Sn), the cluster model of Pt(l 11) was used with some Pt-atoms being substituted by M atoms. Fig. 1 shows... 

According to the current understanding, methanol oxidation proceeds via a dualpath mechanism formaldehyde and formic acid routes. Due to short lifetime most methanolic intermediates are invisible to the current surface spectroscopy techniques however, adsorbed CO and adsorbed formate are well confirmed by IR spectroscopy studies [5, 6]. With that, aU weakly adsorbed intermediates (therefore, soluble) and stronger adsorbed intermediates (carbon monoxide) seem to be recognized. Using a special approach to quantify simultaneously all soluble intermediates by DBMS [7], Zhao et al. [8] confirmed undoubtedly that only three soluble intermediates account for all the faradaic current observed. Hence, in the potential region from 0.65 to 0.80 V (vs. RHE), CO2 formation accounts for about... 

Maiyalagan et al. studied platinum supported on tungsten oxide nanorods that were synthesized using anodic alumnia membrane (Maiyalagan et al., 2008). Their catalyst showed good activity for the MOR, which was attributed to a synergistic effect between the platinum and WO3 and the ability of their catalyst to avoid poisoning that could have otherwise occurred from oxidation of methanol intermediates. 

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