金基氧化物的增强活性,用于氧气的电化学演变
Boon Siang Yeo1, Alexis T Bell
1Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|March 19, 2011
概括
黄金基板上的氧化物薄膜显著增强了氧化演化反应 (OER) 的活性. 这一发现为电催化剂设计提供了新的见解,以实现高效的能量转换.
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
- 表面科学是一门学科.
背景情况:
- 氧进化反应 (OER) 对许多能源技术至关重要,包括水分裂.
- 开发高效和成本效益的OER电催化剂是一个重大挑战.
- 氧化物是有前途的OER催化剂,但它们的性能可能取决于基质.
研究的目的:
- 为了研究电化学氧化演化反应 (OER) 在氧化物薄膜上.
- 探索不同金属基板对OER活动的影响.
- 了解增强开放资源表现背后的机制.
主要方法:
- 扫描电子显微镜 (SEM) 用于表面形态.
- 线性扫描电压测量 (LSV) 和电化学活动的时电压测量.
- 在现场表面增强拉曼光谱 (SERS) 用于操作分析.
- 在0.1M KOH电解液中进行的实验.
主要成果:
- 在Au基板上的氧化物显示,与散装氧化物相比,OER的周转频率高出40倍.
- 随着基质的电子负性,OER活性下降:Au > Pt > Pd > Cu > Co.
- 在Au上的氧化物对OER的活性几乎是散装的三倍.
- 在现场SERS显示的氧化物在OER过程中从Co(3) O(4) 转化为CoO(OH).
结论:
- 基质选择显著影响氧化物OER性能,黄金优越.
- 在黄金上增强的OER活动归因于更高比例的活跃Co ((IV) 站点.
- 一个拟议的机制强调了Co ((IV) 离子在促进OER过程中的作用.
更多相关视频
相关概念视频
Oxidation-Reduction Reactions
Oxidation–Reduction Reactions
Electrochemical Cells
Electrochemical cells are systems that convert chemical energy into electrical energy or use electrical energy to drive chemical reactions. They consist of two electrodes in contact with an electrolyte, where redox reactions enable electron transfer. Most electrochemical cells include two half-cells connected by an external wire for electron flow and a salt bridge for ion flow. The salt bridge contains an electrolyte solution and maintains charge neutrality by allowing ions—not electrons—to...
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...
Voltaic/Galvanic Cells
Spontaneous Chemical Reactions
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
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 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.


