相关实验视频
Updated: Jul 6, 2025

08:43
Potentiodynamic Corrosion Testing
Published on: September 4, 2016
17.6K
使用不钢电极进行酸电位计定位,无需氧化处理
Javier E Vilasó-Cadre1, Daniel Benítez-Fernández2, Ilse A López-Álvarez1
1Institute of Metallurgy, Autonomous University of San Luis Potosi, San Luis Potosi, Mexico.
Turkish journal of chemistry
|January 4, 2024
概括
这项研究表明,即使没有氧化,AISI 304不钢电极也可以为盐酸提供准确的电位计定位结果. 表面特征是实现pH测量Nernstian响应的关键.
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
- 分析化学 分析化学
背景情况:
- 用于电位计定位的标准电极通常涉及贵金属或复杂的制备.
- 研究像不钢这样的替代性,具有成本效益的材料对于分析化学更广泛的可访问性至关重要.
- 电极的表面特性显著影响了它们的电化学反应和Nernstian行为.
研究的目的:
- 评估AISI 304不钢电极的适用性,来自金属加工切片,没有氧化处理,用于电位计定位.
- 描述不钢电极的表面形态和化学成分.
- 为了比较不钢电极与标准玻璃电极在盐酸定位中的性能.
主要方法:
- 使用扫描电子显微镜 (SEM),能量分散式X射线光谱 (EDS),X射线光光谱 (XRF) 和X射线衍射 (XRD) 的表面表征.
- 盐酸 (HCl) 与氧化 (NaOH) 的电位计定位.
- 电极灵敏度的确定和用玻璃电极对标定曲线端点的比较.
主要成果:
- AISI 304不钢电极表现出59.18±0.37mV/pH的可重现的灵敏度.
- 定位曲线显示pH值9.5以上的微小偏差,但产生了准确的终点确定,与玻璃电极一致.
- 确定的盐酸度 (0.0845mol/L) 与标准度 (0.0841mol/L) 非常接近.
- 非氧化电极缺乏晶体氧化物相,而氧化引入了铁和氧化物,增加了钢的结晶性.
结论:
- 即使没有人工氧化,AISI 304不钢电极也可以在pH测量时获得Nernstian响应,这取决于表面特征.
- 材料的表面性能,而不是广泛的氧化,对于可靠的电位计性能至关重要.
- 在任何氧化处理之前,对不钢电极进行校准至关重要,以确认它们固有的Nernstian响应.
相关概念视频
Potentiometry: Types of Electrodes
658
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...
658
Potentiometric Titration: Overview
1.4K
Potentiometric titration is a quantitative analytical technique that determines the concentration of an analyte by measuring the potential difference between the two electrodes in the solution. The endpoint of a potentiometric titration is the point at which there is a significant change in the potential difference. It occurs when the stoichiometric reaction between the analyte and the titrant is complete. The endpoint is usually determined graphically by plotting the measured potential...
1.4K
Potentiometry: Overview
2.1K
Potentiometry is an analytical technique that measures the potential difference between two electrodes in an electrochemical cell without drawing any significant current that could alter the solution's composition. This method employs an indicator electrode, which exchanges electrons with the analyte solution, and a reference electrode with a constant potential. Each electrode is immersed in a solution comprised of two half-cells. In a conventional setup, the reference electrode serves as...
2.1K
Controlled-Potential Coulometry: Electrolytic Methods
173
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...
173
Redox Titration: Overview
2.9K
Redox titration is a chemical analysis technique used to determine the concentration of an unknown substance by measuring the electron transfer in a redox (reduction-oxidation) reaction. The process involves gradually adding a titrant with a known concentration of an oxidizing or reducing agent, to the analyte, the solution with an unknown concentration, until reaching the endpoint, which indicates the completion of the reaction between the two substances. Ensuring the analyte is in a single...
2.9K
Electrodes: Overview
1.7K
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...
1.7K

