反应条件对水合肼还原氧化石墨烯表面官能团还原效率的影响

石墨烯因具有特殊的纳米结构和优异的性能而成为当前的研究热点.实验综合考虑了氧化石墨烯与水合肼的质量配比、反应时间、反应温度和pH值四个因素,采用四因素三水平正交试验系统研究了反应条件对氧化石墨烯各基团还原效率的影响机制.傅里叶红外光谱和透射电子显微镜的结果表明:通过改变反应条件,氧化石墨烯中的主要官能团如羟基、羰基和环氧基均可得到不同程度的还原.进一步利用FT-IR图谱分析软件,采用基线法计算分析表明:(1)氧化石墨烯与水合肼的质量配比是影响还原程度的最主要因素;(2)还原羧基的最佳条件为氧化石墨烯与水合肼质量配比10∶9、反应时间80 min、反应温度100℃、pH值7;还原羟基与环氧基的最佳实验条件相同,均为氧化石墨烯与水合肼质量配比10∶8、反应时间80 min、反应温度100℃、pH值8;(3)可以通过控制反应条件达到采用水合肼选择性还原石墨烯表面羟基、环氧基及羧基的目的.研究结果将为研究化学还原氧化石墨烯机理及制备高性能石墨烯奠定基础.

Influence of Reaction Conditions on the Reduction Efficiency of the Surface Function Groups of Graphene Oxide Reduced by Hydrazine Hydrate

Graphene has attracted great attention due to its nanostructure and excellent property in recent years. In this study, orthogonal experiment is applied to analyse the reduction regulation of different functional groups （ --COOH, C--OH, C--O--C） in GO differed from four factors, hydrazine hydrate dosage, reaction time, reaction temperature and pH value. The reduction of GO is confirmed by Fourier transform infrared （FFIR） and Transmission Electron Microscopy （TEM）. The result suggests that every functional group is reduced to different degree. The characters indicated by FTIR and baseline method show that reduction degree of graphene oxide is mainly limited by hydrazine hydrate dosage. The followings are the best experiment conditions for the reduction of carboxyl：I, the mass ratio of GO to hydrazine is 10： 9;11,reaction time is 80 min;Ⅲ, reaction temperature is 100℃ ;IV, pH value is 7. The optimal reducing conditions for hydroxyl and epoxy group are：I, the mass ratio of GO to hydrazine is 10： 8;11, reaction time is 80 min; Ⅲ, reaction temperature is 100℃ ;IV,pH value is 8. Our results will be beneficial for understanding the mechanism of reduced GO and producing high-quality graphene.