Wu Zuquan, Zhu Shibu, Dong Xiucheng, Yao Yao, Guo Yifan, Gu Shifu, Zhou Zuowan
School of Electrical Engineering and Electrolic Information, Xihua University, Chengdu, Sichuan, 610039, PR China.
Key laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, PR China; Xi'an Aerospace Composites Research Institute, Xi'an, Shaanxi, 710025, PR China.
Anal Chim Acta. 2019 Nov 8;1080:178-188. doi: 10.1016/j.aca.2019.07.021. Epub 2019 Jul 12.
In this paper, a novel graphene oxide (GO)/polyaniline (PANI) sandwich-like nanocomposite has been synthesized by in-situ chemical oxidative polymerization. The GO/PANI is then fabricated onto the interdigitated transducers as sensor for humidity detection. The electrical properties of the thin films are investigated in various relative humidity (RH), including conduction mechanism, sensitivity, reproducibility and humidity hysteresis. The conduction mechanism of the GO/PANI for humidity response is discussed in detail, and the total resistance of GO/PANI is mainly depending on the bulk resistance of PANI. At the lower (60%) RH, the proton hopping transfer plays a very important role for the proton exchange mechanism of GO/PANI thin film. At the higher RH, ionic conduction is not only main conduction process, but also with the proton hopping partially exists for the proton exchange mechanism. Besides, the humidity sensitivity of the thin films enhances with increasing the mass ratio of GO (0, 5, and 50 mg) to PANI due to its larger surface area, hydrophilic functional groups and synergistic effect of π-π* conjugation system, which is also supported by adsorption of QCM humidity response. Meanwhile, the morphology and structure of the thin films are analyzed by fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM) and transmission electron microscope (TEM), respectively.
本文通过原位化学氧化聚合法合成了一种新型的氧化石墨烯（GO）/聚苯胺（PANI）三明治状纳米复合材料。然后将GO/PANI制备在叉指换能器上作为湿度检测传感器。研究了该薄膜在各种相对湿度（RH）下的电学性能，包括传导机制、灵敏度、重现性和湿度滞后。详细讨论了GO/PANI湿度响应的传导机制，GO/PANI的总电阻主要取决于PANI的体电阻。在较低（60%）相对湿度下，质子跳跃转移对GO/PANI薄膜的质子交换机制起着非常重要的作用。在较高相对湿度下，离子传导不仅是主要的传导过程，而且质子交换机制中还部分存在质子跳跃。此外，由于其较大的表面积、亲水性官能团以及π-π*共轭体系的协同效应，薄膜的湿度灵敏度随着GO（0、5和50mg）与PANI质量比的增加而提高，这也得到了石英晶体微天平湿度响应吸附的支持。同时，分别通过傅里叶变换红外光谱（FTIR）、紫外可见光谱（UV-vis）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）对薄膜的形貌和结构进行了分析。
