(145a) Investigating Synergetic Effects Between Deposited PGM Nanoparticles and Transition Metal Carbide Nanotube Support through Surface Characterization and Device Performance

Platinum group metals (PGM) supported on transition metal carbide (TMC) surfaces (PGM/TMC) have been the focus of significant research interest, due to the similar electronic and geometric structures between TMC and Pt.¹ This presentation focuses on probing a new class of electrocatalyst fabrication using high purity β-molybdenum carbide nanotube (Mo₂C) as a support and atomic layer deposition (ALD) as the PGM deposition technique. Lattice spacing analysis and Pt binding energy shift in X-ray photoelectron spectroscopy (XPS) results showed strong interaction between deposited Pt particles and the TMC support. This interaction was correlated with enhanced hydrogen evolution (HER) and hydrogen oxidation reaction (HOR) activity. In addition, significantly increased durability was observed in constant potential electrolysis (CPE) and potential cycling. Finally, the Pt/Mo₂C catalyst performance was systematically evaluated in a device setting for different Pt loadings by applying it in anode and cathode of a proton exchange membrane fuel cell (PEMFC), with accelerated degradation test (ADT) being carried out between 0.6V to 1 V for 30,000 cycles at a scan rate of 500 mV s^-1.² Significantly higher power density was observed in MEAs with Pt/Mo₂C catalysts than 20% Pt/C was observed after the vigorous ADT.

References

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2. B. Han, C. E. Carlton, A. Kongkanand, R. S. Kukreja, B. R. Theobald, L. Gan, R. O'Malley, P. Strasser, F. T. Wagner and Y. Shao-Horn, Energy Environ. Sci., 2014, 8, 258â??266.