Electrochemical investigation on hydride electrode with tungsten carbide additive①
(1. Department of Materials Science and Engineering, Zhejiang University,
Hangzhou 310027, P.R.China;
2. Department of Applied Chemistry, Zhejiang University of Technology,
Hangzhou 310014, P.R.China)
Hangzhou 310027, P.R.China;
2. Department of Applied Chemistry, Zhejiang University of Technology,
Hangzhou 310014, P.R.China)
Abstract: Nano-meter-sized WC powder (1~20 nm) was synthesized by mechanochemical explosion synthesis. The catalytic property of WC powder was discovered to decompose the molecular water and chemical-adsorb H atoms in KOH solution, and accelerate the combination reaction of hydrogen during the cathodic polarization, thus a negative effect on the activation was found because of easy H2emission. Electrochemical impedance spectroscopy (EIS) showed that the adsorbed hydrogen atoms on the surface of WC are first electrochemically oxidized due to their lower chemical bonding, and that the low conductivity of WC powder also increases the internal resistance of electrodes.
Key words: hydrogen storage alloys; tungsten carbide; electrode performances; EIS