AVS 50th International Symposium
    Surface Science Friday Sessions
       Session SS1-FrM

Paper SS1-FrM2
Surface Science Studies of Tungsten Carbides as Potential Electrocatalysts

Friday, November 7, 2003, 8:40 am, Room 327

Session: Catalysis IV: Reactivity of Complex Systems
Presenter: M.B. Zellner, University of Delaware
Authors: M.B. Zellner, University of Delaware
H.H. Hwu, University of Delaware
J.G. Chen, University of Delaware
Correspondent: Click to Email
The purpose of this research is to examine the feasibility of tungsten carbides as direct methanol fuel cell (DMFC) and hydrogen fuel cell electrocatalysts. The motivation to study tungsten carbides stems from the fact that current fuel cells require the use of Pt/Ru anodes, which are expensive and easily poisoned by CO. The successful development of tungsten carbide electrodes as Pt/Ru substitutes can therefore positively influence the commercialization of DMFC and hydrogen fuel cell systems. The reactions of CH@sub 3@OH, H@sub 2@O, H@sub 2@ and CO over tungsten carbide surfaces are studied with temperature-programmed desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS). Thus far, investigations on the C/W(111) and Pt/C/W(111) have been completed. The results show that the carbide surfaces possess characteristics critical to the potential application as DMFC and hydrogen fuel cell anodes. In particular, these surfaces are highly active toward the decomposition of CH@sub 3@OH and H@sub 2@O, and are able to desorb CO at relatively low temperatures. In order to bridge the materials gap from model surfaces to realistic systems, thin films of WC and W@sub 2@C have been deposited on carbon paper and glassy carbon substrates by means of PVD to be tested as electrocatalysts for hydrogen oxidation. Electrochemical testing on the PVD electrocatalysts is currently underway.