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

ABSTRACT: 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)2C, 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.

SUBMITTER: Thode JM

PROVIDER: S-EPMC8588312 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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

Thode James M JM Harris Daniel P DP Wan Cheng C Leonard Brian M BM

Molecules (Basel, Switzerland) 20211102 21

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 ...[more]

PMID: 34771059

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