Ethanol is a sustainable,carbon-neutral transportation fuel.It is an ideal fuel source for direct oxidation
fuel cells for portable and mobile applications,as it offers multiple advantages over hydrogen and
methanol, including ease of transportation,storage and handling as well as higher energy density.
Tremendouseffortshavebeenmadetoimprovedirectethanolfuelcells(DEFC)thatuseprotonexchange
membranes. ThistypeofacidDEFCstillexhibitslowperformance(thestate-of-the-artpeakpower
density is96mWcm2 at 90 1C), despiteemployingexpensiveplatinum-basedcatalysts.However,it
has beenrecentlydemonstratedthattheuseofanionexchangemembranesandnon-platinumcatalysts
in DEFCsenablesadramaticboostinperformance(thestate-of-the-artpeakpowerdensitycanbeas
high as185mWcm2 at 60 1C). ThisarticleprovidesanoverviewofbothacidandalkalineDEFC
technologies bydescribingtheirworkingprinciples,cellperformance,systemefficiency,productsofthe
ethanol oxidationreaction,andcost.RecentinnovationsandfutureperspectivesofalkalineDEFCsare
particularlyemphasized.