Trends in the Hydrogen Evolution Activity of Metal Carbide Catalysts

• Published in: ACS catalysis Vol. 4; no. 5; pp. 1274 - 1278
• Main Authors: Michalsky, Ronald, Zhang, Yin-Jia, Peterson, Andrew A
• Format: Journal Article
• Language: English
• Published: American Chemical Society 02-05-2014
• Subjects: Sabatier principle; sustainable fuels; renewable energy; surfaces; electrocatalysis
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/cs500056u

Metal carbide catalysts are alternative nonprecious electrode materials for electrochemical energy conversion devices, such as for H2 fuel cells or electrolyzers. In this article, we report the experimental exchange current densities for the hydrogen evolution reaction (HER) on eight mono- and bimetallic carbide electrocatalysts and correlate the current densities to hydrogen binding energies that we have calculated via electronic structure computations. We find these materials to have activities higher than those of their parent metals and intermediate between the catalytic activities of the Pt group and early transition-metal surfaces. Increased HER activities on metal carbides relative to their parent metals can be understood with a 3-fold higher sensitivity of metal carbides to the coverage-induced weakening of hydrogen adsorption relative to metal surfaces. The trends presented here can be useful for the design of bimetallic carbide electrocatalysts.