Materials and Process Simulation Center (MSC) and Joint Center for Artificial Photosynthesis (JCAP), California Institute of Technology , Pasadena, California 91125, United States.
J Am Chem Soc. 2017 Jan 11;139(1):130-136. doi: 10.1021/jacs.6b06846. Epub 2016 Dec 21.
Practical environmental and energy applications of the electrochemical reduction of CO to chemicals and fuels require far more efficient and selective electrocatalysts beyond the only working material Cu, but the wealth of experimental data on Cu can serve to validate any proposed mechanisms. To provide design guidelines, we use quantum mechanics to predict the detailed atomistic mechanisms responsible for C and C products on Cu. Thus, we report the pH dependent routes to the major products, methane and ethylene, and identify the key intermediates where branches to methanol, ketene, ethanol, acetylene, and ethane are kinetically blocked. We discovered that surface water on Cu plays a key role in the selectivity for hydrocarbon products over the oxygen-containing alcohol products by serving as a strong proton donor for electrochemical dehydration reductions. We suggest new experiments to validate our predicted mechanisms.
电化学还原 CO 为化学品和燃料的实用环境和能源应用需要远远超过铜这一唯一工作材料的更高效和选择性的电催化剂，但关于铜的丰富实验数据可以用来验证任何提出的机制。为了提供设计指南，我们使用量子力学来预测负责铜上 C 和 C 产物的详细原子级机制。因此，我们报告了主要产物甲烷和乙烯的 pH 依赖性途径，并确定了甲醇、烯酮、乙醇、乙炔和乙烷分支被动力学阻断的关键中间体。我们发现铜表面上的水通过充当电化学脱水还原的强质子供体，在烃产物的选择性方面起着关键作用，超过含氧醇产物。我们建议进行新的实验来验证我们预测的机制。
