Cave Etosha R, Montoya Joseph H, Kuhl Kendra P, Abram David N, Hatsukade Toru, Shi Chuan, Hahn Christopher, Nørskov Jens K, Jaramillo Thomas F
Department of Chemical Engineering, Stanford University, 443 Via Ortega, Shriram Center, Stanford, CA 94305-4125, USA.
Phys Chem Chem Phys. 2017 Jun 21;19(24):15856-15863. doi: 10.1039/c7cp02855e.
In the future, industrial CO electroreduction using renewable energy sources could be a sustainable means to convert CO and water into commodity chemicals at room temperature and atmospheric pressure. This study focuses on the electrocatalytic reduction of CO on polycrystalline Au surfaces, which have high activity and selectivity for CO evolution. We explore the catalytic behavior of polycrystalline Au surfaces by coupling potentiostatic CO electrolysis experiments in an aqueous bicarbonate solution with high sensitivity product detection methods. We observed the production of methanol, in addition to detecting the known products of CO electroreduction on Au: CO, H and formate. We suggest a mechanism that explains Au's evolution of methanol. Specifically, the Au surface does not favor C-O scission, and thus is more selective towards methanol than methane. These insights could aid in the design of electrocatalysts that are selective for CO electroreduction to oxygenates over hydrocarbons.
未来，利用可再生能源进行工业CO电还原可能是一种在室温和常压下将CO和水转化为商品化学品的可持续方法。本研究聚焦于在对CO析出具有高活性和选择性的多晶Au表面上进行CO的电催化还原。我们通过将碳酸氢盐水溶液中的恒电位CO电解实验与高灵敏度产物检测方法相结合，探索了多晶Au表面的催化行为。除了检测到Au上CO电还原的已知产物CO、H和甲酸盐外，我们还观察到了甲醇的生成。我们提出了一种解释Au上甲醇生成的机制。具体而言，Au表面不利于C-O键断裂，因此对甲醇的选择性高于甲烷。这些见解有助于设计对CO电还原为含氧化合物而非碳氢化合物具有选择性的电催化剂。
