Wednesday, 1 June 2016
Exhibit Hall H (San Diego Convention Center)
D. Fang, B. Yang, and S. R. Narayanan (University of Southern California)
Direct methanol fuel cells (DMFCs) are attractive among advanced energy conversion technologies due to the high energy density of methanol, the overall simplicity of system and easy refueling.[1] Although they made an early market entry but did not achieve large-scale commercialization mainly because of the cost, performance and durability issues. The state-of-art DMFC systems are based on the use of Pt-Ru catalyst at the anode, Pt catalyst at the cathode, and a polymer electrolyte membrane separating the two electrodes.[2] Our present study is focused on the anode catalyst, specifically to improve its performance and durability and reduce its cost. To this end, we have examined the use of titanium oxide-ruthenium oxide solid solutions as co-catalyst supports. We have prepared Pt/Ti0.7Ru0.3O2 for use as an anode catalyst. Ti0.7Ru0.3O2 as a co-catalyst support was synthesized in a one-step hydrothermal process and then platinum was deposited using polyol method. The structure of the synthesized catalyst was investigated by XRD, SEM and EDX. Results of steady-state voltammetry suggest that the electrocatalytic activity and stability of the newly synthesized catalysts compare well with the commercially available carbon-supported Pt-Ru catalyst. The Tafel slopes suggested that the well-known bifunctional mechanism for methanol oxidation was operative on the new catalyst as well. With further optimization of this type of catalyst we expect to be able to lower the noble metal content further to enable practical use of these materials in fuel cells.
References
[1] S. Surampudi, S. R. Narayanan, E. Vamos, H. Frank, G. Halpert, A. LaConti, J. Kosek, G. K. Surya Prakash and GA Olah, "Advances in Direct Oxidation Methanol Fuel Cells," Journal of Power Sources, 47, 377-385 (1994)
[2] Handbook of Fuel Cells, “Portable Direct Methanol Fuel Cell Systems”, S. R. Narayanan, T. I.Valdez, in Vol IV Part 1, (Eds. H. Gasteiger, A. Lamm and W. Veilstich), Wiley Interscience ( March 2003)
