在氧进化条件下对La0.6Sr0.4CoO3-δ电催化剂的激活和降解的原子洞察
Moritz L Weber1, Gaurav Lole2,3, Attila Kormanyos4
1Peter Grünberg Institute (PGI-7) and Jülich-Aachen Research Alliance (JARA-FIT), Forschungszentrum Jülich GmbH, Jülich 52425, Germany.
Journal of the American Chemical Society
|September 21, 2022
概括
这项研究揭示了La0.6Sr0.4CoO3-δ矿催化剂在氧化演化反应 (OER) 中如何激活和失活. 表面氧化是活跃的,而氧化的形成导致催化剂失效.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 矿氧化物的稳定性对于水分裂催化剂至关重要.
- 催化剂分解包括离子液和无形化.
- 表面结构的变化会影响矿的电催化剂活性.
研究的目的:
- 了解氧化演化反应 (OER) 条件下的活性表面相形成和稳定性限制之间的相互作用.
- 阐明La0.6Sr0.4CoO3-δ的表面主导的激活和失活机制.
主要方法:
- 多尺度显微镜和光谱.
- 在稳定状态下进行现场电化学分析.
主要成果:
- 已确定演化中的氧化为活性表面物种.
- 确定La-氧化物是导致降解的不活跃物种.
- 观察到Sr液形成混合的活性表面相.
- 从活性CoO (OH) 阶段和La (OH) 3丰富而产生的Co耗尽导致催化剂故障.
结论:
- 在OER期间,La0.6Sr0.4CoO3-δ表现出表面控制的激活和关闭机制.
- 耐用矿催化剂的合理设计需要了解表面阶段演变和降解途径.
更多相关视频
相关概念视频
Thermal and Photochemical Electrocyclic Reactions: Overview
2.4K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.4K
Oxidation-Reduction Reactions
65.6K
Oxidation–Reduction Reactions
65.6K
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
12.6K
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.
12.6K
Electrochemistry: Overview
2.2K
Electrochemistry is the branch of chemistry that studies the relationship between electrical quantities and chemical reactions, particularly oxidation and reduction. Oxidation is the loss of electrons from a substance, whereas reduction refers to the gain of electrons. A substance with a strong electron affinity is called an oxidizing agent (oxidant), and a reducing agent (reductant) is a species that donates electrons. Oxidation and reduction processes are pivotal to electrochemical reactions,...
2.2K
Oxidation and Reduction of Organic Molecules
7.1K
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...
7.1K
Redox Equilibria: Overview
620
A reduction-oxidation reaction is commonly called a redox reaction. In a redox reaction, electrons are transferred from one species to another rather than being shared between or among atoms. The reducing agent or reductant is the species that loses electrons and gets oxidized in the process. The species that gains electrons and gets reduced in the process is the oxidizing agent or oxidant. Redox reactions are represented as two separate equations called half-reactions, where one equation...
620


