Titania, zirconia and hafnia supported ruthenium(0) nanoparticles: Highly active hydrogen evolution catalysts

Designing a cost-effective catalyst with high activity and stability for hydrogen evolution reaction (2H(+) + 2e(-) -> H-2) is a big challenge due to increasing demand for energy. Herein, we report the electrocatalytic activity of glassy carbon electrodes with group 4 metal oxides (TiO2, ZrO2, HfO2) supported ruthenium(0) nanoparticles in hydrogen evolution reaction. Electrochemical activity of modified electrodes is investigated by recording linear sweep voltammograms in 0.5 M H2SO4 solution. The results of electrochemical measurements reveal that among the three electrodes the glassy carbon electrode with Ruci/TiO2 (1.20% wt. Ru) exhibits the highest activity with a relatively small Tafel slope of 52 mV dec(-1), the highest exchange current density of 0.728 mA cm(-2), and the smallest overpotential of 41 mV at j = 10 mA cm(-2). Furthermore, it demonstrates superior stability in acidic solution with an unaltered onset potential for long term electrochemical measurement.


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Citation Formats
E. Demir Arabacı, A. M. Önal, and S. Özkar, “Titania, zirconia and hafnia supported ruthenium(0) nanoparticles: Highly active hydrogen evolution catalysts,” JOURNAL OF COLLOID AND INTERFACE SCIENCE, pp. 570–577, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38935.