石墨烯改性聚丙烯腈基纳米炭纤维的制备及其性能

Preparation and characterization of graphene-reinforced polyacrylonitrile-based carbon nanofibers

以氧化石墨为前驱体,采用真空热膨胀还原法获得了功能化的石墨烯材料。以石墨烯为纳米填料,采用静电纺丝法制备了一系列石墨烯改性聚丙烯腈(PAN)纳米复合纤维,经进一步预氧化和炭化得到纳米炭纤维。使用扫描电镜(SEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、元素分析(EA)、热重(TGA)和差示扫描量热仪(DSC)研究了石墨烯对纳米炭纤维的宏观性能与微观结构的影响。结果表明,加入石墨烯后,PAN纳米纤维中分子取向变大,结晶度下降。对氧化、环化和脱氢反应可产生一定的抑制作用,导致预氧化反应程度下降。同时,石墨烯可作为炭化阶段微晶生长的晶核,有利于碳网平面的快速生长。

Graphene was obtained by vacuum-assisted thermal expansion of graphite oxide followed by a fur- ther thermal annealing. A series of polyacrynitrile （PAN） -based nanofibers with different graphene contents were prepared by electrospinning, using the graphene as the reinforcement. SEM, XRD, P-＇r-IR, TG-DSC and ele- mental analysis were used to investigate the microstructure evolution of the PAN nanofibers during stabilization and carbonization. Results show that the addition of graphene improves the orientation of the PAN molecules, but decreases their crystallinity. This inhibits oxidation, cyclization and dehydrogenation during the oxidative sta- bilization of PAN fibers. Graphene acts as nucleation sites for the growth of graphite crystals along the graphene plane during carbonization.