银电极对二氧化碳在二氧化碳2中的二氧化碳具有高度选择性,这是由于电压依赖动力学和热力学之间的相互作用导致的
Michele Re Fiorentin1, Francesca Risplendi1, Clara Salvini1
1Department of Applied Science and Technology, Politecnico di Torino, corso Duca degli Abruzzi 24, 10129 Torino, Italy.
The journal of physical chemistry letters
|November 11, 2024
概括
银电催化剂有效地将二氧化碳 (CO2) 转化为一氧化碳 (CO) 和有价值的化学物质. 这项研究揭示了银背后的原子级机制.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 电化学减少二氧化碳 (CO2) 为可再生燃料和化学品提供了一条可持续的途径.
- 选择性仍然是一个挑战,的进化往往主导着所需产品的形成.
- 基于白银 (Ag) 的电催化剂对低于-1V的CO生产 (>90%法拉第效率) 显示出高的选择性,与RHE相比.
研究的目的:
- 阐明控制二氧化碳减少银电催化剂高选择性的原子尺度机制.
- 了解不同银面上的关键中间体的电压依赖动力学和热力学.
- 为了将理论计算与实验观察相关联起来.
主要方法:
- 密度函数理论 (DFT) 对Ag{111},Ag{100}和Ag{110) 面的基本步骤的激活自由能量计算.
- 在酸性条件下对多晶银电极进行实验电化学测量.
- 作为应用潜力的函数,分析反应路径和中间覆盖的分析.
主要成果:
- 由于低覆盖率和HCOO*中间体的动力障碍,抑制了酸的形成.
- 对于二氧化碳形成至关重要的*COOH中间体,在-1V以下的应用电位下变得热力学上可获得,并且在动力学上优于的演化,而不是RHE.
- 计算的激活能量与实验观测结果一致,证实了拟议的机制.
结论:
- 银的高二氧化碳选择性源于抑制的酸生产和依赖电压的动力偏好,对于CO的形成而不是的进化.
- 这项研究为二氧化碳转化银电催化剂的选择性提供了原子规模的见解.
- 这种理解可以指导用于可再生燃料和化学合成的更高效的电催化剂的设计.
相关概念视频
Electrodeposition
605
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...
605
Electrolysis
26.0K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
26.0K
Controlled-Potential Coulometry: Electrolytic Methods
144
Controlled-potential coulometry, also known as potentiostatic coulometry, employs a three-electrode system in which the working electrode's potential is precisely regulated using a potentiostat. Platinum working electrodes are utilized for positive potentials, while mercury pool electrodes are favored for extremely negative potentials. The platinum counter electrode is separated from the analyte using a membrane or salt bridge to avoid interference in the analysis.
The chosen potential...
The chosen potential...
144
Electromotive Force
25.9K
Electricity is generated by either electrons or ions flowing through a solution or a conducting medium. This flow of electrons or specifically electrical charge is defined as an electric current. When electrons move through a wire, they generate an electric current. It can be recalled that in a redox reaction, electrons are lost and gained. In the spontaneous redox reaction of zinc with copper, when zinc is immersed in a copper ion solution, a transfer of electrons from one...
25.9K
Voltammetry: Stripping Methods
184
Anodic Stripping Voltammetry (ASV), Cathodic Stripping Voltammetry (CSV), and Adsorptive Stripping Voltammetry (AdSV) are electrochemical techniques used to determine trace amounts of analytes in solution. These methods involve applying a potential to an electrode and measuring the resulting current.
Anodic Stripping Voltammetry (ASV)
ASV is used to determine metals and metalloids at trace levels. It involves two steps: deposition and stripping. First, a negative potential is applied to the...
Anodic Stripping Voltammetry (ASV)
ASV is used to determine metals and metalloids at trace levels. It involves two steps: deposition and stripping. First, a negative potential is applied to the...
184
Standard Electrode Potentials
43.5K
On comparing the reactivity of silver and lead, it is observed that the two ionic species, Ag+ (aq) and Pb2+ (aq), show a difference in their redox reactivity towards copper: the silver ion undergoes spontaneous reduction, while the lead ion does not. This relative redox activity can be easily quantified in electrochemical cells by a property called cell potential. This property is commonly known as cell voltage in electrochemistry, and it is a measure of the energy which accompanies the charge...
43.5K


