在CO2电还原条件下,H和CO共诱导Cu表面的粗化
Zisheng Zhang1, Winston Gee1, Philippe Sautet1,2,3
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90094, United States.
Journal of the American Chemical Society
|May 30, 2024
概括
在电化学条件下对铜 (Cu) 的表面重组是减少二氧化碳的关键. 这项研究揭示了 Cu 表面与吸附 CO 和 H 的动态演变,确定了关键的中间结构及其形成机制.
科学领域:
- 电化学
- 表面科学
- 计算化学
背景情况:
- 铜 (Cu) 电催化剂对于二氧化碳减少至关重要,表面重组被认为是它们反应性的关键因素.
- 表面粗,涉及空隙和原子,是一种拟议的激活机制,但其原子级细节与吸附剂是不清楚的.
研究的目的:
- 在电化学二氧化碳降解条件下研究Cu表面的原子结构和化学演变.
- 阐明表面结构的形成机制及其在电催化中的作用.
主要方法:
- 结合了大规范密度函数理论 (DFT) 和全局优化技术来建模Cu表面重组.
- 使用准动力蒙特卡洛模拟来追踪阴极扫描过程中的动态演变.
- 进行分子动力学模拟和自由能量计算以分析表面物种和反应途径.
主要成果:
- 确定了热力学上不利但动力学上不可避免的CO和H在Cu表面的中间和混合覆盖模式.
- 在表面演化过程中形成的可访问的转移性结构,包括高 Cu*CO 物种.
- 在Cu*CO物种中发现了可信的扩散和二元化机制.
结论:
- 提供了关于二氧化碳电解过程中Cu表面粗和所涉及物种结构的原子性见解.
- 提供可通用的计算方法,用于在非平衡条件下研究混合吸附剂的重组表面.
相关概念视频
Electrodeposition
625
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
625
Catalysis
26.9K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
26.9K
Precipitation and Co-precipitation
1.8K
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
1.8K
Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
4.5K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
4.5K
Reduction of Alkenes: Catalytic Hydrogenation
12.0K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.0K
Corrosion
24.0K
The degradation of metals due to natural electrochemical processes is known as corrosion. Rust formation on iron, tarnishing of silver, and the blue-green patina that develops on copper are examples of corrosion. Corrosion involves the oxidation of metals. Sometimes it is protective, such as the oxidation of copper or aluminum, wherein a protective layer of metal oxide or its derivatives forms on the surface, protecting the underlying metal from further oxidation. In other cases, corrosion is...
24.0K


