Abstract
In an attempt to tailor low-cost, precious-metal-free electrocatalysts for water electrolysis in acid, molybdenum carbide (β-Mo2C) nanoparticles are prepared by in situ carburization of ammonium molybdate on carbon nanotubes and XC-72R carbon black without using any gaseous carbon source. The formation of Mo2C is investigated by thermogravimetry and in situ X-ray diffraction. X-ray absorption analysis reveals that Mo 2C nanoparticles are inlaid or anchored into the carbon supports, and the electronic modification makes the surface exhibit a relatively moderate Mo-H bond strength. It is found that carbon nanotube-supported Mo2C showed superior electrocatalytic activity and stability in the hydrogen evolution reaction (HER) compared to the bulk Mo2C. An overpotential of 63 mV for driving 1 mA cm-2 of current density was measured for the nanotube-supported Mo2C catalysts; this exceeds the activity of analogous Mo2C catalysts. The enhanced electrochemical activity is facilitated by unique effects of the anchored structure coupled with the electronic modification.
Original language | English |
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Pages (from-to) | 943-951 |
Number of pages | 9 |
Journal | Energy and Environmental Science |
Volume | 6 |
Issue number | 3 |
DOIs | |
Publication status | Published - Mar 2013 |
ASJC Scopus subject areas
- Environmental Chemistry
- Renewable Energy, Sustainability and the Environment
- Nuclear Energy and Engineering
- Pollution