A first principles study of direct electrooxidation of aqueous borohydride on Au and Pt surfaces

Direct borohydride fuel cells (DBFC) offer the potential for direct chemical to electrical energy conversion from a high specific energy, water soluble fuel. Power densities similar to those attained from direct methanol fuel cells have been demonstrated, despite substantially less research focus. However, the lack of effective anode materials for the electrocatalysis of borohydride oxidation is the major limitation in advancing the application of these devices. The application of electronic structure modeling to determine the electrocatalytic reaction mechanism and design metal alloy catalysts for increasing the power density and efficiency of DBFC was presented. The development of optimal electrocatalysts for these processes could enable the use of aqueous borohydride solutions as a chemical energy storage vehicle for portable power applications. A mechanistic investigation of BHM₄^- oxidation over the Au(111) surface, identifying stable surface species and rate limiting steps to motivate improved catalyst design, is described. This is an abstract of a paper presented at the AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).