1832
(Physical and Analytical Electrochemistry Division David C. Grahame Award) Kinetics of the Hydrogen Oxidation in Alkaline and Acid Electrolytes
In our presentation, we will compare the kinetics of the H2 oxidation/evolution reaction (HOR/HER) on carbon supported platinum-group metal electrocatalysts in alkaline and acid electrolytes, determined by rotating disk electrode measurements in liquid electrolytes and hydrogen-pump measurements in fuel cells. The so far proposed causes for the »100-fold lower HOR/HER kinetics in alkaline electrolyte are an increased H/metal bond strength [1,4], a change of the reaction mechanism from H+ to H2O activation requiring more oxophilic catalyst surfaces [5], and/or a change of the water configuration at the metal/electrolyte interface [6]. The consistency of these hypotheses with the HOR/HER kinetics on different metal electrodes will be discussed.
References:
[1] J. Durst, A. Siebel, C. Simon, F. Hasché, J. Herranz, H.A. Gasteiger, Energy Environ. Sci. 7(2014) 2255.
[2] J. Durst, C. Simon, A. Siebel, P.J. Rheinländer, T. Schuler, M. Hanzlik, J. Herranz, F. Hasché, H.A. Gasteiger, ECS Trans. 64(3)(2014) 1069.
[3] C.M. Zalitis, D. Kramer, A.R. Kucernak, Phys. Chem. Chem. Phys. 15 (2013) 4329.
[4] Y. Wang, G. Wang., G. Li, B. Huang, J. Pan, Q. Liu, J. Han, L. Xiao, J. Lu, L. Zhuang, Energy Environ. Sci.(2014), DOI: 10.1039/c4ee02564d.
[5] D. Strmcnik, M. Uchimura, C. Wang, R. Subbaraman, N. Danilovic, D. Van der Vilet, A.P. Paulikas, V. Stamenkovic, N. Markovic, Nat. Chem. 5 (2013) 300.
[6] J. Rossmeisl, K. Chan, R. Ahmed, V. Tripkovic, M. Bjorketun, Phys. Chem. Chem. Phys. 15 (2013) 10321.