Ethanol Electro-Oxidation on Pt and PtSn Catalysts

Vigier F, Coutanceau C, Hahn F, Belgsir EM, Lamy C. 2004a. On the mechanism of ethanol electro-oxidation on Pt and PtSn catalysts Electrochemical and in situ IR reflectance spectroscopy studies. J Electroanal Chem 563 81-89. 

Dubau, L., Hahn, F., Coutanceau, C., et al. (2003). On the Structure Effects of Bimetallic PtRu Electrocatalysts Towards Methanol Oxidation, J. Electroanal. Chem., 554-555, pp. 407-415. Vigier, F., Coutanceau C., Hahn, R, etal. (2004), On the Mechanism of Ethanol Electro-oxidation on Pt and PtSn Catalysts Electrochemical and In Situ IR Reflectance Spectroscopy Studies,... 

SPAIR spectra obtained on Pt and PtSn catalysts during ethanol electro-oxidation (Figs. 32 and 33) show that CO2 (wave-number of the absorption band located at 2345 cm ) is only detected at 0.6 V vs. RHE on both Pt and on PtSn catalysts. But, as shown in Fig. 34a, the intensity of the CO2 IR band is higher for PtSn than for Pt at potentials lower than 0.65 V vs. RHE. It is likely that in the detection limit of the IR set up it is difficult to detect CO2 at lower potentials on a PtSn electrode. 

Jiang L, Hsu A, Chu D, Chen R (2010) Ethanol electro-oxidation on Pt/C and PtSn/C catalysts in alkaline and acid solutions. Int J Hydrogen Energy 35(1) 365—372... 

The role of Ru in the mechanism of ethanol electro-oxidation is similar to that of Sn. The adsorption and decomposition of ethanol and its intermediate reaction products happen on Pt active sites, while the dissociative adsorption of water occurs over Sn or Ru sites, to form oxygen-containing surface species. Antolini et al. [24] have shown that the Ru addition of Ru to PtSn catalysts can enhance the catalytic activity of a certain composition. However, this enhancement is related to the Ru/Sn ratio that is present in the alloy, as well as to the synergetic effect of Ru and Sn oxides. 

Wang et al. [140] have studied amorphous CoSn/C alloys decorated with Pt as highly efficient electrocatalysts for ethanol oxidation. The catalysts were prepared using a two-stage chemical synthesis (sol-gel preparation and Steady-state replacement method). XRD results evidenced that the CoSn-base was in the amorphous state, but the characteristic peaks of the Pt fee crystalline structure appeared after Pt deposition. The TEM images confirmed that Pt was deposited onto CoSn/C. The electrochemical measurements showed that the mass activity of the Pt-CoSn/C catalyst was 454.6mA mgp, , which was about 1.71 and 1.74 times those of Pt/C and PtSn/C. The authors attributed this behavior to the possible modification in the Pt electronic structure elicited by the amorphous CoSn alloy. Materials based on amorphous alloys can open new perspectives regarding ethanol electro-oxidation. 

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