在酸性溶液中对Cu{100}) 的酸盐吸附和减少
Sang-Eun Bae1, Karen L Stewart, Andrew A Gewirth
1Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|July 28, 2007
概括
研究了铜 (Cu100) 表面的酸盐降解. 研究人员在使用现场STM和DFT的电化学还原过程中观察到酸盐和酸盐中间体的明显的状结构.
科学领域:
- 电化学 电化学 电化学
- 表面科学是一门学科.
- 计算化学的计算化学
背景情况:
- 酸盐和酸盐是循环和环境修复中的关键中间体.
- 了解它们在金属表面的吸附和减少对于催化应用至关重要.
研究的目的:
- 在酸性溶液中的铜 (Cu100) 表面上研究酸盐吸附和减少的电化学行为.
- 为了阐明吸附酸盐和酸盐中间体的结构变化.
- 为了确定这些物种与铜表面的协调.
主要方法:
- 电化学方法 (循环电压测量,潜在静电降低).
- 在现场电化学扫描道显微镜 (EC-STM) 用于表面成像.
- 表面增强拉曼光谱 (SERS) 用于振动分析.
- 密度函数理论 (DFT) 对电子结构和粘合的计算.
主要成果:
- 酸盐的降解开始于 -0.3 V vs Ag/AgCl,在 -0.58 V 达到峰值.
- 在Cu{100}上观察到酸盐 (2x2) 和酸盐 (c{2x2)) 的显著添加剂,具有潜在依赖的相互转换.
- 在现场STM揭示了整个潜在范围内的动态附加层结构.
- DFT计算证实了酸盐和酸盐对Cu100) 表面的双重协调.
结论:
- 这项研究提供了一个详细的机制理解酸盐降解在Cu100).
- 酸盐和酸盐附加层的结构动态对于减少过程至关重要.
- DFT的结果支持拟议的表面协调和结合.
相关概念视频
Preparation of Amines: Reduction of Oximes and Nitro Compounds
Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
Nitriles to Amines: LiAlH4 Reduction
Nitriles are reduced to amines in the presence of strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution. The reaction requires two equivalents of the reducing agent. The reducing agent acts as a source of hydride ions.
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
Preparation of Amines: Reduction of Amides and Nitriles
Nitriles can be reduced to primary amines using reducing agents like lithium aluminum hydride or catalytic hydrogenation. The reduction introduces an amino group with an extra carbon in the skeleton. Nitriles are formed from the reaction between alkyl halides and sodium cyanide through the SN2 mechanism. Primary alkyl halides are the preferred substrates to prepare nitriles.
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
Electrodeposition
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...


