石墨烯
石墨
电子转移
剥脱关节
动力学
材料科学
氧化还原
反应性(心理学)
玻璃碳
电化学
化学工程
铁氰化物
分析化学(期刊)
化学
纳米技术
光化学
无机化学
电极
循环伏安法
复合材料
物理化学
有机化学
替代医学
病理
工程类
量子力学
冶金
医学
物理
作者
Matěj Velický,Dan F. Bradley,Adam J. Cooper,E.W. Hill,Ian A. Kinloch,Artem Mishchenko,К. С. Новоселов,Hollie V. Patten,Péter S. Tóth,Anna T. Valota,Stephen D. Worrall,Robert A. W. Dryfe
出处
期刊:ACS Nano
[American Chemical Society]
日期:2014-10-13
卷期号:8 (10): 10089-10100
被引量:159
摘要
Understanding of the electrochemical properties of graphene, especially the electron transfer kinetics of a redox reaction between the graphene surface and a molecule, in comparison to graphite or other carbon-based materials, is essential for its potential in energy conversion and storage to be realized. Here we use voltammetric determination of the electron transfer rate for three redox mediators, ferricyanide, hexaammineruthenium, and hexachloroiridate (Fe(CN)63–, Ru(NH3)63+, and IrCl62–, respectively), to measure the reactivity of graphene samples prepared by mechanical exfoliation of natural graphite. Electron transfer rates are measured for varied number of graphene layers (1 to ca. 1000 layers) using microscopic droplets. The basal planes of mono- and multilayer graphene, supported on an insulating Si/SiO2 substrate, exhibit significant electron transfer activity and changes in kinetics are observed for all three mediators. No significant trend in kinetics with flake thickness is discernible for each mediator; however, a large variation in kinetics is observed across the basal plane of the same flakes, indicating that local surface conditions affect the electrochemical performance. This is confirmed by in situ graphite exfoliation, which reveals significant deterioration of initially, near-reversible kinetics for Ru(NH3)63+ when comparing the atmosphere-aged and freshly exfoliated graphite surfaces.
科研通智能强力驱动
Strongly Powered by AbleSci AI