School of Chemical Engineering and Environment, Beijing Institute of Technology , Beijing 100081, China.
ACS Appl Mater Interfaces. 2014 Feb 26;6(4):2248-54. doi: 10.1021/am4057562. Epub 2014 Feb 6.
Graphene-based materials have been widely used as electrode materials of supercapacitors. However, the intrinsic properties related to the capacitance of graphene-based materials essentially need to be clarified. In this work, we have prepared reduced graphene oxide (RGO) through a simple chemical reduction strategy by using hydrazine hydrate as the reducing reagent. The different reduction levels of graphene sheets were successfully realized by controlling the chemical reduction time, and the surface state and density of the functional group were precisely adjusted. We investigated the electrochemical performance of the as-prepared RGO electrode materials. A time dependence of the specific capacitance for the as-prepared RGO electrode was observed. Graphene oxide reduced by hydrazine hydrate at 95 °C for 60 min exhibited the highest weight specific capacitance. The RGO samples were systematically characterized with Fourier transform infrared (FTIR) spectra, X-ray photoelectron spectroscopy (XPS), and Raman measurements. We conclude that the oxygen-containing groups, electrical conductivity, density of defects, and carbon electronic state play substantial roles in deciding the specific capacitance of reduced graphene oxide.
基于石墨烯的材料已被广泛用作超级电容器的电极材料。然而，与基于石墨烯的材料的电容相关的固有性质本质上需要澄清。在这项工作中，我们通过使用水合肼作为还原剂的简单化学还原策略制备了还原氧化石墨烯（RGO）。通过控制化学还原时间，成功地实现了石墨烯片的不同还原水平，并精确调整了表面状态和官能团密度。我们研究了所制备的 RGO 电极材料的电化学性能。观察到所制备的 RGO 电极的比电容随时间的依赖性。在 95°C 下用肼还原 60 分钟的氧化石墨烯表现出最高的重量比电容。用傅里叶变换红外（FTIR）光谱、X 射线光电子能谱（XPS）和拉曼测量对 RGO 样品进行了系统的表征。我们得出结论，含氧基团、电导率、缺陷密度和碳电子态在决定还原氧化石墨烯的比电容方面起着重要作用。
