MWCNT/Nafion/MWCNT复合材料的湿度传感性能研究  

Humidity Sensing Performance of MWCNT/Nafion/MWCNT Composites

作　　者：王延杰[1] 赵世界 盛俊杰 汝杰 赵春 李树勇[3] WANG Yanjie;ZHAO Shijie;SHENG Junjie;RU Jie;ZHAO Chun;LI Shuyong(College of Mechanical and Electrical Engineering,Hohai University,Changzhou 213022,Jiangsu,China;Jiangsu Key Laboratory of Special Robotics Technology,Changzhou 213022,Jiangsu,China;China Academy of Engineering Physics,Mianyang 621900,Sichuan,China)

机构地区：[1]河海大学机电工程学院,江苏常州213022 [2]江苏省特种机器人技术重点实验室,江苏常州213022 [3]中国工程物理研究院,四川绵阳621900

出　　处：《材料导报》2022年第20期213-221,共9页Materials Reports

基　　金：国家重点研发计划“智能机器人”重点专项(2020YFB1312900);国家自然科学基金(51975184);中央高校业务费项目(B210202124,B200202179);国家博士后自然科学基金(2019M661706);江苏省研究生科研与实践创新计划项目(KYCX21_0466)。

摘　　要：为了满足工农业湿度检测的需求,开发新型湿度传感器至关重要。作为湿度传感器的关键部件,湿敏材料的选择直接影响着传感器的使用性能。离子聚合物-金属复合材料(Ionic polymer-metal-composite,IPMC)可制成一种新型柔性传感器,在外界动态湿度作用下,离子聚合物内部的可移动离子将产生定向迁移,形成电势差,从而产生电信号。由于其出色的湿敏特性,IPMC传感器在环境湿度精密监测领域引起了越来越多的关注。但现有离子聚合物复合材料的电极层过于致密,导致复合材料芯层难以与外界环境迅速进行湿度交换;另外,电极层和芯层之间弱的粘附力,导致电极容易脱落。为了解决电极层过于致密的问题,本研究选用多壁碳纳米管(MWCNT)、聚偏氟乙烯(PVDF-HFP)和离子液体(ILs)浇铸具有微孔结构的复合电极层,以提高复合材料芯层与外界环境的湿度交换能力;同时在热压成型过程中,具有离子传输能力的粘结剂被使用在电极层和电解质芯层之间,以增强电极和芯层之间的结合强度。本工作采用溶液铸膜法制备了多壁碳纳米管/聚偏氟乙烯/离子液体(MWCNT/PVDF-HFP/ILs)电极层和全氟磺酸-聚四氟乙烯/离子液体(Nafion/ILs)电解质层,并经叠层热压获得了具有湿敏特性的MWCNT/Nafion/MWCNT复合膜,借助扫描电子显微镜(SEM)、循环伏安曲线(CV)以及电化学阻抗(EIS)等手段表征了复合膜的微观形貌和电化学特性,进一步研究了该复合膜在不同湿度环境下的湿度-电压响应特性、湿敏性能及湿敏机理。研究结果表明:当相对湿度介于0%RH~100%RH时,该湿度传感膜的最快响应时间和恢复时间分别为17 s和58 s,电响应的灵敏度为0.14 mV/%RH,响应速率高达0.277 mV/s。最后,本研究对湿度传感膜在呼吸监测、大坝渗水监测等场合的潜在应用进行了探讨。The development of new humidity sensors is of great importance to meet the industrial and agricultural humidity detection.As a key component of a humidity sensor,the humidity-sensitive material directly affects the performance of the sensor.Ionic polymer-metal-composite(IPMC)can be used as a new type of flexible sensor.The movable ions inside the ionomer will undergo directional migration to form a potential difference under the action of external dynamic humidity,thereby generating an electrical signal.Because of excellent humidity-sensing properties,IPMC sensors have attracted increasing attention in the field of precision monitoring of ambient humidity.However,the electrode layer of the existing IPMC sensors is dense,which makes it difficult for quickly exchange humidity with the external environment.In addition,the weak adhesion between the electrode layer and the ionomer membrane causes the electrode to fall off easily.In order to solve the problem that the electrode layer is too dense,multi-walled carbon nanotubes(MWCNT),polyvinylidene fluoride(PVDF-HFP)and ionic liquids(ILs)have been used to cast the composite electrode layer with microporous structure for quickly exchange humidity with the external environment.Meanwhile,a binder with ion transport ability has been used between the electrode layer and ionomer membrane to enhance the bonding strength of the electrode during the thermoforming process.This work developed a new kind of ionic polymer(MWCNT/Nafion/MWCNT)composite for humidity sensitive film.Firstly,the multiwalled carbon nanotubes/polyvinylidene fluoride/ionic liquid(MWCNT/PVDF-HFP/ILs)electrode layer and perfluorinated sulfonic acid-polytetrafluoroethy-lene/ionic liquid(Nafion/ILs)electrolyte layer were prepared via solution casting method.The MWCNT/Nafion/MWCNT composite film with humidity sensitive properties was assembled by hot-pressing a Nafion/ILs electrolyte layer between two MWCNT/PVDF-HFP/ILs electrode films.Subsequently,the microstructure and electrochemical characteristics of the com

关 键 词：湿度传感 多壁碳纳米管 全氟磺酸树脂(Nafion) 离子液体 

分 类 号：TB332[一般工业技术—材料科学与工程]