多壁碳纳米管/氧化石墨烯/硅橡胶复合薄膜湿敏性能研究

摘要

采用化学修饰的多壁碳纳米管(o-MWC-NTs)与 Hummers 法制备的氧化石墨烯(GO)超声混合,加入室温硫化硅橡胶(RTV),利用溶液共混法制备具有湿敏特性的 o-MWCNTs/GO/RTV 复合薄膜.借助于透射电子显微镜(TEM)、红外吸收光谱(FT-IR)等分析手段分别对化学修饰的多壁碳纳米管及氧化石墨烯进行表征,并对基于 o-MWCNTs/GO/RTV的复合薄膜的湿敏性能及湿敏机理进行了探讨.结果表明,混酸处理后的碳纳米管端口打开,侧壁和开端处产生羧基和羟基等官能团,有利于水分子的吸附,同时也有利于与 GO 表面的基团作用,形成三维的纳微米结构,提高了碳纳米管与硅橡胶基体的相容性,使所制备的 o-MWCNTs/GO/RTV 复合薄膜灵敏度提高.当相对湿度在23％~87％的范围,m (GO)∶m (o-MWCNTs)＝1∶3时,o-MWCNTs/GO/RTV 复合薄膜的湿滞为5％RH,灵敏度为0．3152/％RH,响应时间和恢复时间分别为4和27 s.%A kind of o-MWCNTs/GO/RTV composite film which was sensitive to humidity was prepared by ul-trasonicly mixing multi-walled carbon nanotubes (MWCNTs)which was chemically modified with graphene ox-ide (GO )which was prepared by Hummers method,adding room temperature vulcanized silicone rubber (RTV)in the paper.The modified multi-walled carbon nanotubes and graphene oxide were characterized by TEM and FT-IR.In addition,the sensing property to humidity and its mechanism of o-MWCNTs/GO/RTV composite film were also discussed in the paper.The results show that the carboxyl groups and hydroxyl groups appear on the sidewalls and at the ends of the carbon nanotubes after they were treated by mixed acid,which was benefit to the adsorption of water molecules on it,and also benefit to reaction with the function group on the surface of GO,forming three-dimensional nano-micron structure and improving the compatibility of the car-bon nanotubes and silicone rubber matrix.The results present that the humidity sensitivity of the prepared o-MWCNTs/GO/RTV composite film was increased.The optimum ratio was that GO/o-MWCNTs was 1/3 when the relative humidity was in the range of 23%-87%,the wet hysteresis of o-MWCNTs/GO/RTV humidi-ty films was 5% RH,the sensitivity of humidity film was 0.3152/% RH,and the response time and recovery time were 4 and 27 s respectively.