Enhancing Hydrogen Evolution Activity in Water Splitting by Tailoring Li+-Ni(OH)2-Pt Interfaces
Enhancing Hydrogen Evolution Activity in Water Splitting by Tailoring Li+-Ni(OH)2-Pt Interfaces
复制标题
DOI：
10.1126/science.1211934
复制
发表时间：
2011-12-02
期刊：
影响因子：
56.9
通讯作者：
Markovic, Nenad M.
中科院分区：
文献类型：
--
作者：
Subbaraman, Ram;Tripkovic, Dusan;Markovic, Nenad M.
改善碱性环境中水电化学还原为分子氢的缓慢动力学是降低水-碱和氯-碱电解槽中的高过电位和相关能量损失的一个关键。我们发现，纳米级Ni（OH）（2）簇在铂电极表面上的受控排列表明，相对于最先进的金属和金属氧化物催化剂，催化析氢反应的活性增加了8倍。在双功能效应中，Ni（OH）（2）簇的边缘促进了水的解离和氢中间体的产生，然后吸附在附近的Pt表面上并重新结合成分子氢。这些氢中间体的生成可以通过Li+诱导的HO-H键的不稳定化进一步增强，导致活性总增加10倍。
Improving the sluggish kinetics for the electrochemical reduction of water to molecular hydrogen in alkaline environments is one key to reducing the high overpotentials and associated energy losses in water-alkali and chlor-alkali electrolyzers. We found that a controlled arrangement of nanometer-scale Ni (OH)(2) clusters on platinum electrode surfaces manifests a factor of 8 activity increase in catalyzing the hydrogen evolution reaction relative to state-of-the-art metal and metal-oxide catalysts. In a bifunctional effect, the edges of the Ni(OH)(2) clusters promoted the dissociation of water and the production of hydrogen intermediates that then adsorbed on the nearby Pt surfaces and recombined into molecular hydrogen. The generation of these hydrogen intermediates could be further enhanced via Li+-induced destabilization of the HO-H bond, resulting in a factor of 10 total increase in activity.