High Activity Carbide Supported Catalysts for Water Gas Shift

Nanostructured carbides are refractory materials with high surface areas that could be used as alternatives to the oxide materials that are widely used as support materials for heterogeneous catalysts. Carbides are also catalytically active for a variety of reactions, offering additional opportunities to tune the overall performance of the catalyst. In this paper we describe the synthesis of molybdenum carbide supported platinum (Pt/Mo2C) catalysts and their rates for the water gas shift reaction. The synthesis method allowed interaction of the metal precursor with the native, unpassivated support. The resulting materials possessed very high WGS rates and atypical Pt particle morphologies. Under differential conditions, rates for these catalysts were higher than those for the most active oxide-supported Pt catalysts and a commercial Cu-Zn-Al catalyst. Experimental and computational results suggested that active sites on the Pt/Mo2C catalysts were located on the perimeter of the Pt particles and that strong interactions between Pt and the Mo2C surface gave rise to raft-like particles.