Alkaline media ethylene glycol oxidation

In an acidic medium, a PEMFC fed with ethanol allows power densities up to 60 mW cm to be reached at high temperatures (80-120 °C), but this needs platinum-based catalysts, which may prevent wider applications for portable electronic devices. On the other hand, in an alkaline medium, the activity of non-noble catalysts for ethanol or ethylene glycol oxidation and oxygen reduction is sufficient to reach power densities of the order of 20 mW cm at room temperature. This opens up the hope of developing SAMFCs that are particularly efficient for large-scale portable applications. 

Demarcormay L, Brimaud S, Coutanceau LJM (2007) Ethylene glycol oxidation in alkaline medium at multi-metallic Pt based catalysts. J Electroanal Chem 601 169-180... 

Elshafei AA, Shabanah HM, Moussa MNH (1993) Catalytic influence of underpotentially deposited submonolayers of different metals in ethylene-glycol oxidation on various noble-metal electrodes in alkaline-medium. J Power Sources 46(1) 17-27... 

Elshafei AA,EhnaksoudSAA,Fouda AS (1995) Noble-metal-modified glassy-carbrai electrodes for ethylene-glycol oxidation in alkaline-medium. J Electroanal Chem 395(1-2) 181-187... 

Although the Bonnemann method is very interesting by allowing to vary and to control easily the composition and the nanostructure of the catalyst and is adapted to the preparation of real fuel cell electrodes, it displays also some limitations. For example, bismuth-containing colloids could not be prepared with the Bonnemann method, and even in presence of platinum salts. Moreover, the presence of bismuth hinders the reduction of platinum salts [59], However, platinum-bismuth is a good catalyst for ethylene glycol electro-oxidation in alkaline medium [59-62], Moreover, colloid of tin alone could not be obtained, and the reaction was only possible by coreduction in the presence of a platinum salt. Then, other colloidal methods should be developed keeping in mind the necessity of a similar flexibility as that of the Bonnemann method. 

As an example, platinum-bismuth catalysts with different atomic ratios have been prepared by the water-in-oil method and tested for the ethylene glycol electro-oxidation in alkaline medium [59],... 

Kadirgan F, Beden B, Lamy C (1983) Electrocatalytic oxidation of ethylene-glycol. 2. Behavior of platinum-Ad-atom electrodes in alkaline-medium. J Electroanal Chem 143(1-2) 135-152... 

All the Pt-based catalysts described in acidic medium can be applied to ethanol electro-oxidation in alkaline medium, too. Nevertheless, Pd is a metal that has displayed good performance in basic medium, mainly due to its low tolerance to CO poisoning in the Pd-sites, thereby favoring the rapid oxidation of this molecule to CO2. Because the properties of Pd are similar to those of Pt, some literature works have been devoted to the substitution of Pt with Pd during the preparation of electrocatalysts. Shen and Xu [45-47] have studied the oxidation of alcohols such as methanol, ethanol, glycerol, and ethylene glycol on... 

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