摘要
以纤维素纳米纤丝和多壁碳纳米管为主要原料,采用一步水热法、冰模板法冷冻干燥以及高温煅烧法,成功制得具有多级连通类木材管胞状孔结构的氮掺杂碳点的复合衍生碳气凝胶,并对其微观形貌、化学结构、比表面积和孔隙度进行表征。通过循环伏安测试、恒电流充放电测试、交流阻抗测试和长循环测试等电化学表征手段分析其电化学性能。结果表明:碳气凝胶表面经高温煅烧得到大量氮、氧杂原子掺杂的碳微颗粒和碳微绒毛,提高了碳气凝胶的缺陷态结构含量和比表面积,其比表面积可达377.9 m^(2)/g;在三电极测试体系下,比电容可达121.8 F/g(测试电流密度为0.2 A/g,电压窗口为-0.2~0.8 V);在2 A/g的电流密度下,进行5000次充放电循环后,电容保持率可达131.7%。衍生碳气凝胶独特的微观形貌和高比表面积,为能量存储提供了更快速和便捷的电子/离子传输通道、优异的导电性和更高的比容量,为超级电容器等储能器件电极材料的设计提供了木基生物质资源利用的新思路。
Supercapacitors have developed rapidly in the energy field in recent years due to the fact that the high energy density of secondary batteries and the high-power density of conventional capacitors are combined in supercapacitors.In the study of electrode materials for supercapacitors,the application of various types of carbon materials,which have superior electrical conductivity,porous structure,and chemical stability,to the construction of electrode materials is an important path to effectively improve the electrical performance of supercapacitors.Among them,aerogel materials constructed from cellulose nanofilaments and a carbon-rich biomass material derived from wood,have the advantages of high specific surface area,multi-level pore structure,environmental friendliness,and recyclability,which are high-quality raw materials for the preparation of carbon aerogels instead of petrochemical products.In this study,cellulose nanofibril(CNF)and multi-walled carbon nanotube(MWCNT)were used as precursors.Carbon aerogels derived from carbon dots,multi-walled carbon nanotubes,and cellulose nanofibers were prepared successfully by one-step hydrothermal method,ice template freeze-drying,and high temperature calcination.The carbon aerogel with nitrogen-doped carbon dots(NCDs)has a wood tracheid-like pore structure.The morphology,chemical structure,specific surface area,and porosity of the prepared carbon aerogel were characterized.The electrochemical performances were analyzed by cyclic voltammetry,constant current charge-discharge,electrochemical impedance spectroscopy(EIS),and cycle performance test.During the high-temperature calcination,a large number of NCDs were induced by MWCNT to in-situ grow into carbon microparticles and micro-villis containing a large amount of nitrogen and oxygen heteroatoms on the carbon aerogel.It significantly increased the specific surface area and the number of defect state structures of carbon aerogels,providing faster and more convenient electron/ion transport channels,excellent electrical
作者
陈雪琦
唐启恒
常亮
郭明辉
CHEN Xueqi;TANG Qiheng;CHANG Liang;GUO Minghui(Research Institute of Wood Industry,Chinese Academy of Forestry,Beijing 100091,China;School of Material Science and Engineering,Northeast Forestry University,Harbin 150040,China)
出处
《林业工程学报》
CSCD
北大核心
2023年第4期110-120,共11页
Journal of Forestry Engineering
基金
国家林业和草原局林业和草原青年拔尖人才项目(2022132007)。
关键词
碳点
纤维素纳米纤丝
碳气凝胶
超级电容器
电化学性能
carbon dots
cellulose nanofibril
carbon aerogel
supercapacitor
electrochemical performance
