Highly active and durable nanostructured molybdenum carbide electrocatalysts for hydrogen production
Highly active and durable nanostructured molybdenum carbide electrocatalysts for hydrogen production
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DOI：
10.1039/c2ee23891h
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发表时间：
2013-03-01
影响因子：
32.5
通讯作者：
Adzic, R. R.
中科院分区：
文献类型：
--
作者：
Chen, W. -F.;Wang, C. -H.;Adzic, R. R.
在尝试定制低成本的，不含贵金属的电催化剂用于酸中的水电解的过程中，碳化钼（beta-Mo 2C）纳米颗粒通过在碳纳米管和XC-72 R炭黑上原位碳化铵来制备，而不使用任何气态碳源。通过热重分析和原位X射线衍射研究了Mo 2C的形成。X射线吸收分析表明，Mo 2C纳米颗粒镶嵌或锚定在碳载体中，电子修饰使表面呈现出相对适中的Mo-H键强度。结果表明，碳纳米管负载的Mo 2C在析氢反应中表现出比本体Mo 2C更优越的上级电催化活性和稳定性.对于纳米管负载的Mo 2C催化剂，测得驱动1 mA cm（-2）电流密度的过电位为63 mV;这超过了类似的Mo 2C催化剂的活性。锚定结构与电子修饰相结合的独特效应促进了增强的电化学活性。
In an attempt to tailor low-cost, precious-metal-free electrocatalysts for water electrolysis in acid, molybdenum carbide (beta-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 Mo2C 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.