柔性高比表静电纺碳纳米纤维制备及其吸附VOCs性能研究  

Study on the Preparation of Flexible Electrospun Carbon Nanofibers with High Specific Surface Area and Their Adsorption Performance for VOCs

作　　者：贾震震 李一鸣 郑智宏 张静云 程璇[1] 郑煜铭[2] 邵再东 JIA Zhenzhen;LI Yiming;ZHENG Zhihong;ZHANG Jingyun;CHENG Xuan;ZHENG Yuming;SHAO Zaidong(College of Materials,Xiamen University,Xiamen 361005,Fujian,China;CAS Key Laboratory of Urban Pollutant Conversion,Institute of Urban Environment,Chinese Academy of Sciences,Xiamen 361021,Fujian,China;Fujian Provincial Key Lab of Bag Filter Materials and Technology(Xiamen Zhongchuang Environmental Technology Co.,Ltd.),Xiamen 361101,Fujian,China)

机构地区：[1]厦门大学材料学院,福建厦门361005 [2]中国科学院城市环境研究所中国科学院城市污染物转化重点实验室,福建厦门361021 [3]福建省袋滤材料与技术重点实验室(厦门中创环保科技股份有限公司),福建厦门361101

出　　处：《材料导报》2024年第18期239-246,共8页Materials Reports

基　　金：国家重点研发计划(2022YFC3702800);福建省袋滤材料与技术重点实验室(厦门中创环保科技股份有限公司)开放课题。

摘　　要：碳纳米纤维的直径小,比表面积大,是一种高效的气体吸附材料。但是,碳纳米纤维通常需要经过过程复杂、成本较高并且环境影响大的活化热处理工艺来提高其多孔特性。本研究以聚酰胺酸(PAA)和聚甲基丙烯酸甲酯(PMMA)为原料,通过共混静电纺丝和热亚胺化获得聚酰亚胺(PI)纳米纤维,再经一步炭化法制备高比表面积的柔性碳纳米纤维,并系统分析碳化条件对柔性PI/PMMA基碳纳米纤维的形貌特征、物理化学性质和VOCs吸附性能的影响规律。结果表明:1000℃碳化条件下制备的PI/PMMA基碳纳米纤维具有最大的比表面积(1047.5 m^(2)·g^(-1))和孔容(0.61 cm^(3)·g^(-1))。吸/脱附动力学实验表明,PI/PMMA基碳纳米纤维比表面积和微孔体积的增大显著加快了吸/脱附过程中甲苯的传质速率。静态吸附实验表明,PI/PMMA基碳纳米纤维在25℃下对甲苯的吸附容量高达6.25 mmol·g^(-1),吸附等温线较符合Langmuir模型,对苯、丙酮、三氯甲烷和甲醇等典型挥发性有机化合物(VOCs)同样具有良好的吸附性能,表明其是一种潜在的优异的VOCs吸附材料。动态吸附实验显示,PI/PMMA基碳纳米纤维对1137 mg·m^(-3)的甲苯气体的吸附容量高达2.97 mmol·g^(-1),经过五次吸脱附循环,其吸附量仍保持在初始值的91%,表现出优异的循环稳定性。本研究制备的柔性PI/PMMA基碳纳米纤维是一种性能优异的VOCs吸附材料,在低浓度VOCs去除方面具有很大的应用潜力。Carbon nanofibers have the advantages of small fiber diameter and large specific surface area,making them an efficient gas adsorption material.However,carbon nanofibers with enhanced porous properties are often prepared via a complex carbonization and activation process,which is costly and time consuming.In this study,highly porous polyimide(PI)polymethyl methacrylate(PMMA)based flexible carbon nanofibers were directly prepared by one-step carbonization.The PI nanofibers were obtained through co-electrospinning polyamide acid(PAA)and PMMA followed by thermal imidization.The effects of carbonization conditions on the morphological characteristics,physicochemical properties and volatile organic chemicals(VOCs)adsorption performance of flexible PI/PMMA-based carbon nanofibers were systematically analyzed.The results showed that the PI/PMMA-based carbon nanofibers prepared at 1000℃had the largest specific surface area(1047.5 m^(2)·g^(-1))and pore volume(0.61 cm^(3)·g^(-1)).The adsorption/desorption kinetics showed that the increase of specific surface area and the number of micropores in PI/PMMA-based carbon nanofibers significantly accelerated the mass transfer rate of toluene during the adsorption/desorption process.The results of static adsorption experiments showed that the adsorption capacity of the prepared PI/PMMA-based carbon nanofibers for toluene was as high as 6.25 mmol·g^(-1)at 25℃,and the adsorption isotherms were well fitted with Langmuir model.In addition,the PI/PMMA-based carbon nanofibers also had good adsorption performance for various other typical VOCs such as benzene,acetone,chloroform and methanol.The adsorption capacity for 1137 mg·m^(-3)toluene analyzed via dynamic adsorption was as high as 2.97 mmol·g^(-1).After 5 cycles of adsorption and desorption,the adsorption capacity remained at 91%,indicating an excellent cycle stability.This flexible PI/PMMA-based carbon nanofibers with excellent VOCs adsorption performance are promising for the removal of low concentration VOCs.

关 键 词：静电纺丝 碳纳米纤维 VOCS 气体吸附 

分 类 号：TB34[一般工业技术—材料科学与工程]