Fuel Cells: Direct Ethanol

Abstract

Alcohols, and methanol in particular, have been investigated as potential fuels for use in direct fuel cells for mobile applications. However, the fuel cell community is now turning its attention to ethanol as the fuel of choice because of benefits such as renewability and low fuel toxicity. Nonetheless, the direct ethanol fuel cell (DEFC) has several technological problems that are more tenacious than the direct methanol fuel cell (DMFC). Among them, the slow anode kinetics presents the greatest challenge since it results in poor fuel cell performance in applications. Current anode catalysts, which are primarily an extension of the DMFC anode catalysts, do not prove to be very effective in delivering high current densities or sufficiently high conversions. Thus, there is a need to modify existing catalysts or to develop new catalysts that are able to oxidize ethanol molecules more effectively and more completely. This article provides a succinct account of the various catalysts currently in use at the anode and cathode of a DEFC, with emphasis on the anode catalysts used in an acidic environment, which require the most improvement. The use of cocatalysts, promoters, and catalyst support as well as catalysts used for ethanol oxidation in alkaline media are also briefly discussed.

Effects of Alloyed Metal on the Catalysis Activity of Pt for Ethanol Partial Oxidation: Adsorption and Dehydrogenation on Pt3M (M = Pt, Ru, Sn, Re, Rh, and Pd)

“…There have been a few review papers on the recent progress on the electro-catalysts for DEFC. 2–4 Pt-based alloy catalysts have been recognized to better catalyze the oxidation of ethanol than Pt alone. Of the Pt-based alloy catalysts PtM(M=Ru, Sn, Ir, Bi, Pd, Ru, Rh, etc.…”

“…Thus, it has been a challenge to find an efficient electrocatalyst to increase the electroreactivity of ethanol. A few review articles have been published on recent progress on electrocatalysts for DEFCs. − Pt-based alloy catalysts have been recognized as better catalysts for the oxidation of ethanol than Pt alone. Of the Pt-based alloy catalysts PtM (M = Ru, Sn, Ir, Bi, Pd, Ru, Rh, etc.…”