在纳米金上的CO自促进氧化:三角Au3活性位点和CO诱导的O-O裂变
Chunyan Liu1, Yingzi Tan, Sisi Lin
1Department of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, Xiangtan University, Hunan Province 411105, People's Republic of China.
Journal of the American Chemical Society
|January 25, 2013
概括
建议在金纳米集群上进行一氧化碳 (CO) 氧化的一种新机制. 二氧化碳分子通过削弱三角形黄金位点上的氧键来促进自身的氧化,有效地形成二氧化碳.
科学领域:
- * 不同质的催化.
- *纳米材料科学是一门学科.
- * 表面的化学成分
背景情况:
- * 黄金纳米集群是CO氧化过程中的活性催化剂.
- * 了解反应机制对于催化剂设计至关重要.
- * 现有的机制无法完全解释纳米金的观测活动.
研究的目的:
- * 在纳米金上研究CO氧化机制.
- * 阐明黄金集群大小和结构的作用.
- * 提出一种新的催化途径.
主要方法:
- *密度函数理论 (DFT) 的计算.
- * 波恩-奥本海默分子动力学 (BOMD) 模拟.
- *对黄金集群 (0.30.8 nm) 和支系统 (Au) /MgO,双层Au/TiO2) 的研究.
主要成果:
- * 确定了一种三分子朗格穆尔-欣舍尔伍德机制,称为CO自我促进氧化.
- *一个三角形的Au(3) 位点通过共吸收的CO的电友性攻击促进了O-O键裂变.
- * 极低的能量障碍导致自发的二氧化碳形成.
- * 该机制对于具有可用的三角 Au ((3) 位点的系统是通用的.
- *CO还促进其他氧化反应,如 styrene 氧化.
结论:
- *CO自促进氧化是金纳米结构上CO氧化的一个基本途径.
- *三角形Au(3) 图形是这种增强反应性的关键.
- * 这种机制为黄金催化和催化剂设计提供了新的见解.
相关概念视频
Oxidative Cleavage of Alkenes: Ozonolysis
In ozonolysis, ozone is used to cleave a carbon–carbon double bond to form aldehydes and ketones, or carboxylic acids, depending on the work-up.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
Oxidation-Reduction Reactions
Oxidation–Reduction Reactions
Oxidation and Reduction of Organic Molecules
Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions, which occur at the same time. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called redox reactions.
The removal of an electron from a molecule, results in a...
The removal of an electron from a molecule, results in a...
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.


