摘要
对氧化石墨进行了热解和H2还原处理,通过元素分析、X射线衍射分析、傅立叶变换红外光谱仪(FT IR)分析和粉末电阻率测定,初步探讨了氧化石墨的分子组成、官能团、晶体结构和电导率随还原温度的变化规律。结果表明:对经220℃热处理的热解氧化石墨进行H2还原处理时,随着还原温度的升高,还原氧化石墨中氧元素的质量百分含量减小,晶体结构逐渐回复为石墨的晶体结构,但存在明显的晶粒细化现象;随温度的升高,还原氧化石墨的电导率增大,并在500℃时达到最大值6.67S/cm;当还原温度超过500℃时,由于层间距增大及晶粒进一步细化,其电导率又逐渐降低;热解氧化石墨在H2中的还原过程可以分为两个阶段,第Ⅰ阶段主要发生—CO基团和C—OH基团的还原反应,第Ⅱ阶段残余的C—OH基团被还原。
Reduced graphite oxide at different temperatures was synthesized from graphite oxide by high temperature treatment and reduction under H_2. Composition, functional group, crystal structure and conductivities of reduced graphite oxide at different temperatures were investigated by elemental analysis, XRD, FT-IR and automatic multi-function resistivity measuring instrument. The results show that with the increasing of temperature oxygen content of pyrolytic graphite oxide at 220℃(PGO220) decreases. Although the grain is refined, the crystal structure is similar with that of graphite. The conductivity of reduction graphite oxide increases with the increasing temperature and at 500℃ it reaches the maximum, 6.67S/cm. when above 500℃ its conductivity decreases because of excursions and grain refining.There are two stages in the process of GO reduction. During the first stage —CO and C—OH are reduced, then the residual C—OH is reduced during the second stage.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2005年第6期940-945,共6页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目(50372019)
关键词
氧化石墨
还原
晶体结构
电导率
graphite oxide
reduce
crystal structure
conductivity
