在性电化学系统中识别"Cu"状态的局部原子环境
Lars Ostervold1, Raheleh Daneshpour1, Madelyn Facchinei1
1Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802-1503, United States.
ACS applied materials & interfaces
|May 31, 2023
概括
氧化水氧化铜 (CuOOH) 是氧化铜催化剂在氧化演化反应 (OER) 中的活性物种. 运行拉曼光谱和DFT计算在氧化条件下确定了这种活性形式.
科学领域:
- 电化学和催化剂的应用
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 基于氧化铜 (CuO) 的催化剂对氧演化反应 (OER) 有效.
- 在OER期间活性铜的确切化学形式仍未确定.
- 了解活性物种对于优化OER催化剂性能至关重要.
研究的目的:
- 在氧化演化反应 (OER) 中识别活性铜物种.
- 为了阐明活性铜物种的电子结构.
- 为了将实验观察结果与理论计算相关联.
主要方法:
- 在OER条件下操作拉曼光谱来监测催化剂变化.
- 密度函数理论 (DFT) 计算来模拟拉曼光谱和电子结构.
- 电化学实验以验证拟议的活性物种.
主要成果:
- 观察到一个独特的拉曼特征,表明在高氧化OER条件下存在"Cu3+"物种.
- DFT的计算确定了CuOOH作为一个潜在的活性物种,与实验中的拉曼签名相匹配.
- 电化学验证证实CuOOH,可能是CuO上的表面氧化物,作为活性形式.
结论:
- 基于CuO的OER催化剂中的活性物种被确定为氧化水氧化铜 (CuOOH).
- 电子结构表现出Cu2+d9L的特征,而不是一个正式的Cu3+状态.
- 这项工作阐明了铜催化OER的基本机制.
相关概念视频
Electrodeposition
683
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...
683
Ladder Diagrams: Redox Equilibria
491
Ladder diagrams are useful tools for understanding redox equilibrium reactions, especially the effects of concentration changes on the electrochemical potential of the reaction. The vertical axis in the redox ladder diagrams represents the electrochemical potential, E. The area of predominance is demarcated using the Nernst equation.
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
491
Controlled-Potential Coulometry: Electrolytic Methods
218
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...
218
Electrogravimetric Analysis: Overview
281
Electrogravimetric analysis measures the weight of an analyte deposited electrolytically onto a suitable working electrode. This method involves applying a potential to a pre-weighed electrode submerged in a solution, which results in the desired substance being deposited through reduction at the cathode or oxidation at the anode. The electrode's weight is recorded after deposition, and the difference in weight gives the analyte's weight in the solution.
To test the completeness of the...
To test the completeness of the...
281
Electrolysis
26.9K
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...
26.9K
Voltammetric Techniques: Cyclic Voltammetry
571
Cyclic voltammetry (CV) is an electrochemical technique used to investigate the redox properties of a chemical species. It involves measuring the current response of an electrochemical cell as a function of the applied potential. The setup for cyclic voltammetry typically consists of a working electrode, a reference electrode, and a counter electrode—all immersed in an electrolyte solution. The working electrode is where the redox reaction of interest occurs, while the reference electrode...
571


