通过控制的氧化状态来增强酸氧演化活动
Xue Han1, Tianyou Mou1, Sinwoo Kang1
1Brookhaven National Laboratory, Chemistry Division, UNITED STATES OF AMERICA.
Angewandte Chemie (International ed. in English)
|June 11, 2025
概括
在氧化化 (oxi-TiN) 上的高氧化 (IrOx) 纳米颗粒显著提高了酸氧演化反应 (OER) 的性能. 这种新型催化剂超过了商业二氧化,满足了水电解的关键能源目标.
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
- 催化剂是一种催化剂.
背景情况:
- 具有高氧化状态的氧化物 (IrOx) 对于提高酸氧演化反应 (OER) 性能至关重要.
- 开发高效和稳定的催化剂对于先进的水电解技术至关重要.
研究的目的:
- 在氧化条件下,开发在化 (TiN) 上支的超小IrOx纳米颗粒,在氧化条件下形成氧改TiN (oxi-TiN).
- 研究高氧化Irδ+ (δ > 4) 的形成及其对OER活动的影响.
- 为了证明催化剂在质子交换膜水电解器中的性能,并阐明其增强活性背后的机制.
主要方法:
- 在TiN上合成超小的IrOx纳米颗粒.
- TiN的表面氧化形成氧气修饰的TiN (oxi-TiN).
- 在现场进行X射线吸收光谱 (XAS) 检测,以确认Ir.的氧化状态.
- 密度函数理论 (DFT) 计算以了解电子结构和反应机制.
- 在质子交换膜水电解器中的性能测试.
主要成果:
- 该IrOx/oxi-TiN催化剂使得高氧化Irδ+ (δ > 4) 的形成成为可能.
- 与具有相似稳定性的商业IRO2相比,IrOx/oxi-TiN具有更高的Ir质量活性.
- 在一个质子交换膜水电解器中,催化剂在3 A cm-2时达到1.88 V的低电位,达到美国能源部2025年目标.
- 在现场的XAS和DFT计算证实,Irδ+和界面氧的高氧化状态对于降低OER过量的潜力至关重要.
结论:
- 在oxi-TiN上的超小IrOx纳米颗粒对酸性OER非常有效.
- 在IrOx/oxi-TiN接口形成高度氧化的Irδ+ (δ > 4) 是优质催化活性的关键.
- 这项工作为设计先进的电催化剂提供了一条途径,通过控制金属氧化状态来有效地分解水.
相关概念视频
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
9.9K
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.
9.9K
Oxidation-Reduction Reactions
64.4K
Oxidation–Reduction Reactions
64.4K
Redox Titration: Other Oxidizing and Reducing Agents
249
Besides iodine, other oxidizing or reducing agents can serve as titrants in redox titrations. Common oxidizing titrants include KMnO4, cerium(IV), and K2Cr2O7. The choice of oxidizing titrants depends on factors like stability, cost, analyte strength, and reaction rate between the analyte and titrant. KMnO4 is a strong oxidizing titrant that reduces from Mn(VII) to Mn(II) in a highly acidic solution, simultaneously oxidizing the analyte to a higher oxidation state. In this case, KMnO4 acts as a...
249
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
11.0K
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.
11.0K
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
5.7K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
5.7K
Redox Equilibria: Overview
540
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...
540


![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)