以壳粉为原料,在碱性条件下制备液化物树脂(LPF),经静电纺丝、固化、碳化得到多孔碳纳米纤维(PCNF)。探讨了聚乙烯醇(PVA)用量对纺丝液特性及纤维形貌的影响。同时,采用傅里叶变换红外光谱(FTIR)、热重分析仪(TG)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、全自动比表面积及孔隙分析仪(BET)等方法对不同碳化温度下的样品进行表征。结果表明:少量PVA可以明显提高LPF的纺丝性,且随PVA用量的增加,纤维的形貌更规整、直径更小;随着碳化温度的升高,LPF/PVA纤维逐渐裂解,多数官能团消失,基体为多苯稠环结构;同时,层间距d(002)逐渐减小,平面尺寸Lc和Lc/d(002)增加,纤维内部的类石墨结构逐渐向更规整、有序的石墨微晶结构转变;当碳化温度为800℃时,LPF/PVA的含碳量达55%以上,随着PVA用量的增加,纤维的比表面积明显增大且多以微孔为主,当PVA用量为8%时,得到比表面积为590m^2/g的多孔碳纳米纤维。
Porous carbon nanofiber(PCNF)was prepared through electrospinning,curing and carbonization with liquid phenolic resin and polyvinyl alcohol(PVA)as raw materials.The influence of PVA content on the properties of electrospun solution and fiber morphology was discussed.The obtained fibers were characterized by FTIR,TG,SEM,XRD and BET techniques.The results showed that a small amount of PVA could obviously improve the spin-ability of LPF.With the increase of PVA content,the morphology of fiber is more regular and the diameter is smaller.With the carbonization temperature increased,the LPF/PVA fiber pyrolysed gradually,most functional groups were eliminated,and the matrix turned into benzene fused ring structure.At the same time,the value of d(002)decreased,while the values of Lcand Lc/d(002)increased,which implied that arrangement of graphite crystal among of LPF/PVA fiber layers was regularly piled up,and both the carbon net structure and the graphitoidal degree of fiber were developed and improved remarkably.When the carbonization temperature was 800 ℃,the carbon content of LPF/PVA fiber was higher than 55%.The specific surface and pore volume of LPF/PVA fiber increased gradually with the PVA content and the main structure was microporous.When the content of PVA was 8%,a PCNF structure with a surface area of 590m^2/g could be obtained.