相关实验视频
Updated: Jan 10, 2026

05:03
Precise Electrochemical Sizing of Individual Electro-Inactive Particles
Published on: August 4, 2023
1.6K
电催化中的阴离子效应的通用模型
1McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States.
JACS Au
|November 28, 2025
概括
电解质通过改变催化剂表面的电场,显著影响电催化剂速率. 这种静电框架解释了阴离子效应,改善了催化剂的设计和性能.
科学领域:
- 电化学 电化学 电化学
- 表面科学是一门学科.
- 催化剂是一种催化剂.
背景情况:
- 在电催化过程中,电解质通常被认为是惰性的.
- 观察到的催化速率往往对离子同一性敏感,缺乏统一的解释.
- 以前的解释涉及不同反应系统的各种物理现象.
研究的目的:
- 为理解电催化中的电离子效应提供一个一般的静电框架.
- 解释电极表面的阴离子排列如何改变接口电场.
- 确定观察阴离子效应的标准.
主要方法:
- 开发基于静电学的理论模型.
- 分析电极表面的阴离子排列 (大小,形状,溶度,包装).
- 考虑电场对吸附中间体和过渡状态的影响.
主要成果:
- 阴离子排列决定了界面电场强度,影响了反应能量.
- 当运行电位是零总电荷电位的负值,反应步骤对场敏感时,就会观察到阴子效应.
- 该框架协调了不同催化剂和电解质的活性和选择性的以前不一致的趋势.
结论:
- 静电模型为电催化中的阴离子效应提供了统一的解释.
- 它为设计新的催化剂和电解质提供了概念和预测价值.
- 承认电场在催化中的作用为改善活动和选择性开辟了道路.
更多相关视频
相关概念视频
Electrolytes: van't Hoff Factor
36.2K
Colligative Properties of Electrolytes
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
36.2K
Common Ion Effect
45.5K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
45.5K
Ionic Strength: Effects on Chemical Equilibria
2.5K
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary...
In this solution, the primary...
2.5K
Formation of Complex Ions
25.6K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
25.6K
Standard Electrode Potentials
49.7K
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...
49.7K
Factors Affecting Activity Coefficient
1.5K
The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size.
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
1.5K

