An ingenious strategy for improving humidity sensing properties of multi-walled carbon nanotubes via poly-L-lysine modification
An ingenious strategy for improving humidity sensing properties of multi-walled carbon nanotubes via poly-L-lysine modification
复制标题
通过聚-L-赖氨酸修饰提高多壁碳纳米管湿度传感性能的巧妙策略
DOI：
10.1016/j.snb.2019.03.070
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发表时间：
2019-06-15
影响因子：
8.4
通讯作者：
Tai, Huiling
中科院分区：
文献类型：
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作者：
Zhao, Qiuni;Yuan, Zhen;Tai, Huiling
多壁碳纳米管（MWCNTs）作为一种导电性好但亲水性差的材料，很难直接应用于湿度传感领域。为了获得具有良好半导体特性和湿度传感性能的MWCNTs，研制了聚l -赖氨酸（PLL）改性的MWCNTs复合膜用于湿度检测。在相对湿度（RH）为0 ~ 91.5% RH的室温（25℃）条件下，研究了该传感器的湿度传感性能。由于PLL具有丰富的亲水性官能团和导阻效应，基于MWCNTs/PLL薄膜的电阻式湿度传感器在91.5% RH下具有659.97%的良好湿度传感响应。特别是，湿度传感器的电阻显示出明显的正湿度系数（PHC），这是由锁相环的膨胀效应引起的。最后，进一步研究了湿度传感器在皮肤湿度、婴儿尿布润湿、空间湿度分布和人体呼出气体的实时监测等方面的各种潜在应用，为湿度传感器的实用化提供了一个巧妙的策略。
Multi-walled carbon nanotubes (MWCNTs) as one of excellent conductive and poor-hydrophilicity materials are difficult to be directly used in humidity sensing field. In order to obtain MWCNTs with both good semiconducting characteristic and improved humidity sensing performances, MWCNTs composite film via poly-L-lysine (PLL) modification was developed for humidity detection. The humidity sensing properties of the as-fabricated sensor were investigated at room temperature (25 degrees C) within the relative humidity (RH) range from 0 to 91.5% RH. Due to abundant hydrophilic functional groups and conduction-blocking effect of PLL, the resistive-type humidity sensor based on MWCNTs/PLL film exhibits a good humidity sensing response of 659.97% at 91.5% RH. Especially, the resistance of the humidity sensor displays a clear positive humidity coefficient (PHC) that caused by the swelling effect of PLL. Finally, various potential applications of the humidity sensor were further performed for the real-time monitoring of skin humidity, baby diaper wetting, spatial humidity distribution and human exhaled breath, which provide an ingenious strategy for the practicability of the humidity sensor.