基于Ni的阳极的动态潜力-pH图表,用于在Cl-杂质存在的情况下实现持久的氧气进化
Hiroki Komiya1, Swastik Laha2, Keisuke Obata1
1Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
The journal of physical chemistry letters
|June 9, 2025
概括
酸盐电解质显著减少海水电解系统中的基于的阳极腐蚀. 这可以防止由化物离子引起的降解,提高系统的耐用性.
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
- 腐蚀科学 腐蚀科学
背景情况:
- 离子 (Cl-) 腐蚀是长期海水电解中阳极材料面临的主要挑战.
- 基于的电极容易在海洋环境中降解.
研究的目的:
- 为了研究Ni基电极在各种缓冲电解质中的腐蚀行为.
- 了解酸盐电解质对化物诱导的腐蚀的保护机制.
主要方法:
- 动态潜力-pH (普尔贝克斯) 图分析.
- 在酸盐,碳酸盐和酸盐缓冲溶液中进行电化学腐蚀试验.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 与性条件相比,NiFeOx/Ni电极在轻度酸性到中性pH下显示出更快的降解.
- 腐蚀速率受到溶解的离子物种和表面化合物的热力学稳定性的影响.
- 酸盐电解质有效地抑制了由于形成稳定,低可溶性Ni-PO4复合物的腐蚀.
- DFT的计算证实了表面上化物相比酸盐的优先吸附.
结论:
- 以酸盐为基础的电解质为缓解海水电解中的化物腐蚀提供了一个有希望的策略.
- 离子的热力学稳定性和吸附行为是保护阳极的关键.
- 了解这些机制对于开发用于海洋应用的耐用电极材料至关重要.
相关概念视频
Ladder Diagrams: Redox Equilibria
537
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+...
537
Standard Electrode Potentials
45.1K
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...
45.1K
Electrodeposition
733
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...
733
Electrolysis
27.3K
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...
27.3K
The Nernst Equation
42.3K
Nonstandard Reaction Conditions
The interconnection between standard cell potentials and various thermodynamic parameters such as the standard free energy change ΔG° and equilibrium constant K has been previously explored. For example, a redox reaction involving zinc(II) and tin(II) ions at 1 M concentration with Eºcell = +0.291 V and ΔG° = −56.2 kJ is spontaneous.
The interconnection between standard cell potentials and various thermodynamic parameters such as the standard free energy change ΔG° and equilibrium constant K has been previously explored. For example, a redox reaction involving zinc(II) and tin(II) ions at 1 M concentration with Eºcell = +0.291 V and ΔG° = −56.2 kJ is spontaneous.
42.3K
Concentration Cells
23.3K
A concentration cell is a type of a voltaic cell constructed by connecting two almost identical half-cells, both based on the same half-reaction and using the same electrode, differing only in the concentration of one redox species. A concentration cell's potential, therefore, is determined only by the concentration difference of the particular redox species.
Consider the following voltaic cell:
Consider the following voltaic cell:
23.3K


