参考电极和DRT的组合使用用于解AEM电解器损失
Suhas Nuggehalli Sampathkumar1, Thomas Benjamin Ferriday2, Samaneh Daviran1
1Group of Energy Materials, École polytechnique fédérale de Lausanne (EPFL), Rue de l'Industrie 17, Sion, Valais 1951, Switzerland.
概括
阳离子交换膜水电解器 (AEMWE) 有望降低成本,但面临耐用性挑战. 本研究详述了AEMWE组件分析,揭示了长期运行过程中的性能限制和降解机制.
科学领域:
- 电化学
- 材料科学
- 化学工程
背景情况:
- 阴离子交换膜水电解剂 (AEMWEs) 是使用非贵金属催化剂和性电解剂的高性价比替代品.
- 尽管AEMWE具有优势,但在实现长期耐用性,高电流密度和稳定的膜性能方面仍然存在挑战.
- 在长时间运行时对AEMWE组件进行全面的结构电化学分析是有限的.
研究的目的:
- 进行商业AEMWE的详细结构和电化学表征.
- 使用双参考电极,将全电池性能与内在半电极性能相关联.
- 在运行压力下提供NiFeOx阳极和Raney阴极的完整材料分析.
主要方法:
- 电化学表征包括线性扫描电压测量 (LSV) 和电化学阻抗光谱 (EIS).
- 使用双参考电极设置来区分半电池性能.
- 对阳极和阴极材料进行断层和光谱检查.
- 在1.0 A cm−2,60 °C,1.0 M KOH下进行长期运行试验 (1000小时).
主要成果:
- 在2.2V (环境) 达到1.0A cm−2和2.0V (60°C) 达到1.1A cm−2的全电池性能,在1.0A cm−2时达到74.5%的高温效率.
- 经过230小时的运行,观察到极化阻力显著增加,与因膜降解而导致的持续MEA性能改善形成对比.
- 与气泡形成和中/高频过程 (> 50 Hz) 相关的低频阻抗峰值,以传输电荷和离子传输.
- 与Raney阴极相比,NiFeOx阳极表现出更高的电荷传递动力.
结论:
- 双参考电极研究和DRT分析对于隔离AEMWE的性能损失至关重要.
- 虽然膜降解在短期内改善了MEA的整体性能,但却导致了长期的运营挑战.
- 了解单个电极性能和降解途径是推进AEMWE技术的关键.
相关概念视频
Electrogravimetric Analysis: Overview
333
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...
333
Electrodes: Overview
1.9K
Electrochemical measurements are conducted in an electrochemical cell composed of various components that control and measure the current and potential. One fundamental component is electrodes, conductive materials that enable electron transfer reactions at their surfaces.
There are two main types of electrodes in electrochemical cells. The first type, known as the working or indicator electrode, has a potential that is sensitive to the analyte's concentration and reacts to changes in...
There are two main types of electrodes in electrochemical cells. The first type, known as the working or indicator electrode, has a potential that is sensitive to the analyte's concentration and reacts to changes in...
1.9K
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
Electrodeposition
709
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...
709
Potentiometry: Types of Electrodes
919
Reference electrodes serve as a stable reference point for potentiometric measurements, while indicator and working electrodes react to variations in the composition of a solution.
The Standard Hydrogen Electrode (SHE) is a widely used reference electrode that maintains zero potential across all temperatures. However, its need for a continuous hydrogen gas supply renders it impractical for everyday use.
An alternative to SHE is the Saturated Calomel Electrode (SCE). This electrode features an...
The Standard Hydrogen Electrode (SHE) is a widely used reference electrode that maintains zero potential across all temperatures. However, its need for a continuous hydrogen gas supply renders it impractical for everyday use.
An alternative to SHE is the Saturated Calomel Electrode (SCE). This electrode features an...
919


