两种干燥方式对碳纳米管/纳米纤维素气凝胶结构与性能的影响  

Effects of Two Drying Methods on the Structure and Properties of Nanocellulose/Carbon Nanotubes Aerogels

作　　者：常焕君 张龙飞[1,2] 吕少一 王思群[3] CHANG Huan-jun;ZHANG Long-fei;LYU Shao-yi;WANG Si-qun(Research Institute of Wood Industry,Chinese Academy of Forestry,Beijing 100091,China;Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;Centre for Renewable Carbon,University of Tennessee,Knoxville 37996,USA)

机构地区：[1]中国林业科学研究院木材工业研究所,北京100091 [2]林业资源高效加工利用协同创新中心,南京林业大学,江苏南京210037 [3]美国田纳西大学再生碳中心,诺克斯维尔37996

出　　处：《木材科学与技术》2022年第5期43-49,共7页Chinese Journal of Wood Science and Technology

基　　金：林业公益性行业科研专项“纳米纤维素绿色制备和高值化应用技术研究”(201504603)。

摘　　要：采用超临界干燥和冷冻干燥法制备了碳纳米管/纳米纤维素气凝胶,探讨两种干燥方法对气凝胶的微观形貌、化学结构、结晶性、比表面积、孔隙结构和电化学性能的影响规律。结果表明:两种干燥方法对气凝胶微观结构、结晶性、比表面积、孔隙结构和电化学性能影响显著,而对其化学结构影响有限;超临界干燥的SWCNT/CNF气凝胶呈现纤丝状多孔网络结构,结晶度为56.41%,比表面积和孔体积分别为266.39 m^(2)/g和0.77 cm^(3)/g,面积比电容为265.46 mF/cm^(2);而冷冻干燥的样品则为片状结构,结晶度为31.37%,比表面积和孔体积分别为47.78 m^(2)/g和0.15 cm^(3)/g,面积比电容为176.04 mF/cm^(2);超临界干燥的气凝胶具有更高的结晶度、更大的比表面积和孔体积,能够为电极材料提供更多的活性位点,提升其电化学性能。本研究为制备高性能电极材料提供了研究思路。Carbon nanotubes/nanocellulose aerogels were prepared by supercritical drying and freeze drying respectively. The effects of two drying methods on the morphology, chemical structure,crystallinity, specific surface area, pore structure and electrochemical properties of aerogel were investigated. The results showed that the two drying methods had a significant effect on the microstructure, crystallinity, specific surface area, pore structure and electrochemical properties of aerogel, but had limited effect on its chemical structure. The supercritical drying SWCNT/CNF aerogel showed a fibrous porous network structure with a crystallinity of 56.41%, a specific surface area of 266.39 m^(2)/g, a pore volume of 0.77 cm^(3)/g and an area specific capacity of 265.46 mF/cm^(2). However, the freeze-dried sample had a flake structure with 31.37 % crystallinity, 47.78 m^(2)/g specific surface area, 0.15cm^(3)/g pore volume and 176.04 m F/cm^(2)area specific capacity, respectively. The supercritical drying aerogel had higher crystallinity, specific surface area and pore volume, which could provide more active sites for electrode materials and improve their electrochemical performance. This study provided a research idea for the preparation of high-performance electrode materials.

关 键 词：气凝胶 纳米纤维素 碳纳米管 超临界干燥 冷冻干燥 

分 类 号：TQ352.79[化学工程] TB34[一般工业技术—材料科学与工程] S781[农业科学—木材科学与技术]