Electrocatalysis of oxygen reduction with platinum supported on molybdenum carbide–carbon composite

• New molybdenum carbide–carbon composite support is reported.
• The synthesis of the newly support was thoroughly studied.
• Addition of Pt to the support shows enhanced catalytic activity when compared to Pt on XC72.
• The results are supported by theoretical calculation that also suggests enhanced durability.

Molybdenum carbide–carbon (MoC0.56–C) composite was synthesized using a polymer assisted deposition (PAD) technique, and studied as possible catalyst support. The electrocatalysis of oxygen reduction reaction (ORR) was studied with Pt deposited on the newly developed support. The ORR activity of Pt/MoC0.56–C is far better than that of standard support, 140 A gPt−1 at 0.9 V vs. RHE compared to 68 with A gPt−1 with Pt/XC-72. This high activity with the potential of increased durability of MoC0.56–C composite material, when compared to commercial carbon supports, is a significant step in PEM cells technology. These results are complemented by theoretical calculations which show a favorable electronic interaction of the Pt and the composite material. The MoC0.56–C composite was obtained using a one-step PAD synthesis technique at 800 °C. From XRD analysis, this composite material contains 56.7% MoC0.56 with an average crystallite size of 1 nm and a balance of amorphous carbon. SEM–EDAX pictures revealed that the support is composed of two separated phases, the amorphous carbon and the molybdenum carbide. Platinum nano-particles were deposited onto the support and served as catalyst for oxygen reduction for the evaluation of this composite material as a possible catalyst support in fuel cells and metal-air batteries.

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