Studies On Nanostructural Anodic Catalysts For Direct Ethanol Fuel Cell

Recently developed direct methanol fuel cell has been received widespread attention due to the abundant source, the low price, the safety of the storage and transportation of the fuel. However, the question of the toxicity of methanol remains crucial, such as portable electronic devices(laptop computers, cellular phones). Another alternative is to use other alcohols presenting negligible or very low chemical toxicity which is essential, at least for some applications. On the other hand, certain countries with abundant biomass resources are producing significant amounts of ethanol, which is a convenient, cheap and relatively nontoxic liquid fuel. As an alternative fuel, ethanol is safer and exhibits higher energy density than methanol. Thus, it is possible to be applied for the fuel in the fuel cell. But, one of the problems is that the oxidation of ethanol is not as easy as the oxidation of methanol, mainly because of the presence of the C-C bond. It is clear that ethanol electro-oxidation involves more intermediates and products than that of methanol, and thus the actual performance obtained are slightly lower than those observed with methanol. It is key techniques in DEFC to find with the composite catalysts have good electrocatalytic activity and resistant ability to poisoning for the ethanol oxidation. The good electrocatalytic active nanoTiO₂-CNT/Pt, nanoTiO₂-CNT-PAn/Pt composite nanostructural catalysts were prepared by the precursor Ti(OEt)₄ directly hydrolyzed and cyclic voltammetry electrodepositing method. TEM, XRD and SEM results show the size, crystallinity and surface character of the catalysts. The electrocatalytic activitics and stability for the ethanol oxidation were evaluated with the electrochemical techniques. The main result obtained are as follows:Part one: electrochemical deposition method by cyclic voltammetry(CV) to prepare the nanoTiO₂-CNT/Pt, and the composite electrocatalysts were characterized to study those composition and those electrochemical behavior by CV. The electrocatalytic activitics and stability for the ethanol electrooxidation...