Methanol electro-oxidation

Preparation of Pt/mesoporous carbon catalysts and their application to the methanol electro-oxidation... 

Fig. 4 shows the current density over the supported catalysts measured in 1 M methanol containing 0.5 M sulfuric acid. During forward sweep, the methanol electro-oxidation started to occur at 0.35 V for all catalysts, which is typical feature for monometallic Pt catalyst in methanol electro-oxidation [8]. The maximum current density was decreased in the order of Pt/CMK-1 > Pt/CMK-3 > Pt/Vulcan. It should be noted that the trend of maximum current density was identical to that of metal dispersion (Fig. 2 and Fig. 3). Therefore, it is concluded that the metal dispersion is a critical factor determining the catalytic performance in the methanol electro-oxidation.

Mesoporous carbon materials were prepared using ordered silica templates. The Pt catalysts supported on mesoporous carbons were prepared by an impregnation method for use in the methanol electro-oxidation. The Pt/MC catalysts retained highly dispersed Pt particles on the supports. In the methanol electro-oxidation, the Pt/MC catalysts exhibited better catalytic performance than the Pt/Vulcan catalyst. The enhanced catalytic performance of Pt/MC catalysts resulted from large active metal surface areas. The catalytic performance was in the following order Pt/CMK-1 > Pt/CMK-3 > Pt/Vulcan. It was also revealed that CMK-1 with 3-dimensional pore structure was more favorable for metal dispersion than CMK-3 with 2-dimensional pore arrangement. It is eoncluded that the metal dispersion was a critical factor determining the catalytic performance in the methanol electro-oxidation. 

EFFECT OF CATALYST STRUCTURE AND COMPOSITION METHANOL ELECTRO-OXIDATION... 

A bifunctional catalyst should be able to activate two different reaction steps (methanol and water adsorption and surface reaction between adsorbed species), and so active sites with different properties are necessary. As an example, investigations of possibihty of enhancing activity with regard to methanol electro-oxidation with Pt-Ru-based electrodes are of great interest with regard to improving the electrical efficiency of DMFCs. Several approaches have been considered the effect of Pt-Ru... 

Chu D, Gilman S. 1996. Methanol electro-oxidation on unsupported Pt-Ru alloys at different temperatures. J Electrochem Soc 143 1685-1690. 

Gasteiger HA, Markovic N, Ross PN, Caims EJ. 1994. Temperature-dependent methanol electro-oxidation on well-characterized FT-Ru alloys. J Electrochem Soc 141 1795-1803. 

Vidal F, Busson B, Tadjeddine A. 2005. Probing electronic and vibrational properties at the electrochemical interface using SFG spectroscopy Methanol electro-oxidation on Pt(llO). Chem Phys Lett 403 324-328. 

Figure 3.35 Potential dependence or the ft) integrated band intensity of the linear COad< derived from methanol at 0,4 V vs. RHE in I M CH3OH/0.5M H SO and (2) the methanol electro-oxidation current observed after the adsorption of methanol at 0.4 V. From K. Kunimatsu, Berichte der Bunsen-Ceseiischaft jur Phy-sitcafische Chemie. 1900.94. 1025 1030-...

Tong, X., et ah, Enhanced catalytic activity for methanol electro-oxidation of uniformly dispersed nickel oxide nanoparticles - carbon nanotube hybrid materials. Small, 2012. 

T. Page, R. Johnson, J. Hormes, S. Noding, and B. Rambabu, A study of methanol electro-oxidation reactions in carbon membrane electrodes and structural properties of Pt alloy electro-catalysts by EXAES, J. Electroanal. Chem. 485, 34-41 (2000). 

T. H. M. Housmans, A. H. Wonders, and M. T. M. Koper. Structure sensitivity of methanol electro-oxidation pathways on platinum An online electrochemical mass spectrometry study. Journal of Physical Chemistry B 110 (2006) 10021-10031. 

The catalytic properties of Pt and Ru particles on T102-CNT catalysts in the methanol electro-oxidation were investigated by He et Pt and Ru nanoparticles, approximately of 3 nm in diameter, were uniformly electro-deposited on the as synthesized Ti02-supported C nanotubes. An enhanced and stable catalytic activity was obtained in the electro-oxidation of methanol due to the uniformly dispersed Pt and Ru nanoparticles on the... 

Mallouk, T. E., Reddington, E., Pu, C., Ley, K. L., Smotkin, E.S., Discovery of methanol electro-oxidation catalysts by combinatorial analysis. In Fuel Cell Semi-... 

The effect of the structure of the catalysts on their electroactivity was first evaluated by CO stripping. The oxidation of a saturated layer of adsorbed CO occurs at lower potentials on the codeposited Pt0 8+Ru0 2/C catalyst than on the Pt0 8Ru0 2/C coreduced one, and the mixture of a Pt/C catalyst with a Ru/C catalyst gives the worst activity (Figure 9.16a). The activity for methanol electro-oxidation is also higher at the nonalloyed codeposited catalyst than at the alloyed... 

H. Gasteiger, N. Markovic, P. N. Ross, and E. J. Cairns, J. Electrochem. Soc. 141 1296 (1994). Temperature-dependent methanol electro-oxidation on well-characterized Pt-Ru alloys. 

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