Anode catalysts glycerol

Matsuoka et al. [8] tested ADAFCs formed by Pt-Ru/C as anode catalyst, Pt/C or Ag/C as cathode catalyst, and the AHA membrane by Tokuyama Co. The cells operated at 50 °C and were fuelled with four polyhydric alcohols and methanol for comparison. These alcohols (1 M) were dissolved in 1 M KOH aqueous solution. The maximum power densities were in the order of ethylene glycol > glycerol > methanol > erythritol > xylitol. The direct ethylene glycol fuel cell showed the highest power density. AlkaUne direct alcohol fuel cells using silver as a cathode catalyst showed good performance however, the open-circuit voltage of a cell with... 

Anode Catalysts for Direct Polyol Fuel Cells (Ethylene Glycol, Glycerol) Cogenerate Electricity 179... 

Xin, L., Zhang, ZY., Wang, Z.C., and Li, W.Z (2012) Simultaneous generation of mesoxalic acid and electricity from glycerol on a gold anode catalyst in anion-exchange membrane fuel cells. ChemCatChem, (S), 1105-1114. 

Qi, J., Xin, L., Chadderdon, D.J., Qiu, Y., Jiang, Y., Benipal, N., Liang, C.H., and Li, W.Z. (2014) Electrocatalytic selective oxidation of glycerol to tartronate on Au/ C anode catalysts in anion exchange membrane fuel cells with electricity cogeneration. Applied Catalysis B Environmental, 154, 360-368. 

Fig. 4.1 Important aspects for the anode performance towards the alcohol electro-oxidation (i) interaction between the catalyst surface and the alcohol molecules, (ii) interaction between the catalyst surface and the resulting adsorbed fragments from the original alcohol molecules, and (iii) surface oxides formation from the water splitting and reaction products desorption. Glycerol is taken as an example of alcohol molecule M metal atom...

Table 6.12 summarizes the results obtained with AEM for higher alcohols, most of them for commercial membranes. A-006 Tokuyama membrane exhibit the best performances for glycerol in active cells with Pd catalyst in the anode. 

The dilution of Pd with non-noble metals in a smart catalytic architecture capable of rapidly and stably oxidizing alcohols on anode electrodes would knock down the main barriers to the commercialization of direct alcohol fuel cells (DAFC), especially those fed with primary alcohols, hi er than methanol, and polyalcohols. Indeed, apart from methanol for which there exist platinnm based catalysts capable of prodncing cnrrent densities of several tens of mW cm, the higher alcohols like ethanol and polyalcohols like glycerol are difficnlt to oxidize on platinum or platinum alloyed with either noble or non-noble metals. 

The anode and cathode catalyst were Pt-Ru/C (4 mg cm" ) and Pt/C (1 mg cm ) (C = Vulcan XC-72) from E-TEK (USA), respectively, and the solid electrolyte was a Toknyama AHA membrane. At 45°C, the peak power densities with methanol and glycerol were 8 mW cm at 28 mA cm and 6 mW cm at 27 mA cm, respectively. Scott et al. have investigated the performance of an active DMFC using a Morgane -ADP membrane from Solvay... 

In fuel cells working with a liquid fuel, usually an alcohol such as methanol (a direct methanol fuel cell - DMFC), ethanol (a direct ethanol fuel cell - DEFC), glycerol (a direct glycerol fuel cell - DGEC), etc., in addition to the necessity to activate the ORR at the cathode, the alcohol oxidation reaction at the anode also involves a high overpotential. This high overpotential is mainly due to the formation, after dissociative adsorption of the alcohol at the catalyst surface, of poisoning species which block the catalytic surface the main one adsorbed is carbon monoxide. ... 

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