Synthesis of Metastable Ternary Pd-W and Pd-Mo Transition Metal Carbide Nanomaterials

Research and catalytic testing of platinum group transition metal carbides have been extremely limited due to a lack of reliable, simple synthetic approaches. Powder samples have been reported to phase separately above 1%, and only thin-film samples have been reported to have appreciable amounts of precious metal doping. Herein, we demonstrated, through the simple co-precipitation of Pd and W or Mo precursors and their subsequent annealing, the possibility to readily form ternary carbide powders. During the investigation of the Pd-W ternary system, we discovered a new hexagonal phase, (PdW)(2)C, which represents the first non-cubic Pd ternary carbide. Additionally, the solubility of Pd in the Pd-W-C and Pd-Mo-C systems was increased to 24 and 32%, respectively. As a potential application, these new materials show an enhanced activity for the methanol oxidation reaction (MOR) compared to industrial Pd/C.

Automated summary

Research on platinum group transition metal carbides has been limited due to a lack of reliable synthetic approaches. The simple co-precipitation of Pd and W or Mo precursors followed by annealing can lead to the formation of ternary carbide powders, with increased solubility of Pd in the systems. These new materials show enhanced activity for the methanol oxidation reaction compared to industrial Pd/C.