Li Wei, Jin Xin, Han Xing, Li Yeran, Wang Wenyu, Lin Tong, Zhu Zhengtao
School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.
School of Materials Science and Engineering, Tiangong University, Tianjin 300387, China.
ACS Appl Mater Interfaces. 2021 Apr 28;13(16):19211-19220. doi: 10.1021/acsami.0c22938. Epub 2021 Apr 16.
A porous and microstructure piezoresistive material composed of polydimethylsiloxane (PDMS) and multiwalled carbon nanotubes (MWCNTs) was designed and prepared for a flexible and highly sensitive pressure sensor over a wide detection range. The microstructure was patterned on the surface of the partially cured PDMS/MWCNTs/NaCl mixture by imprinting a nonwoven fabric. After curing and dissolving the NaCl powders, the porous and surface microstructure PDMS/MWCNT film was obtained. Two PDMS/MWCNT films were stacked together and sandwiched between two copper foil electrodes, in which the two microstructure surfaces were in contact with the electrodes. Due to the synergistic effects of the combination of the porous structure and surface microstructure, the flexible sensor had highly sensitive response over a wide pressure range from 1 Pa to 100 kPa. Under the small pressure, the high sensitivity was achieved by the change in contact areas between the electrodes and the surface microstructures; at high pressure up to 100 kPa, the sensor retained its high sensitivity because of the porous structure of the piezoresistive PDMS/MWCNT material. Additionally, the sensor had fast response speed and good durability. The piezoresistive pressure sensors based on the porous and microstructure PDMS/MWCNTs were demonstrated in detection of sound, monitoring of human activities, and array mapping of the spatial pressure distribution.
设计并制备了一种由聚二甲基硅氧烷（PDMS）和多壁碳纳米管（MWCNT）组成的多孔微结构压阻材料，用于制作在宽检测范围内具有高灵敏度的柔性压力传感器。通过压印无纺布在部分固化的PDMS/MWCNT/NaCl混合物表面形成微结构。固化并溶解NaCl粉末后，得到多孔且具有表面微结构的PDMS/MWCNT薄膜。将两片PDMS/MWCNT薄膜堆叠在一起，并夹在两个铜箔电极之间，其中两个微结构表面与电极接触。由于多孔结构和表面微结构相结合的协同效应，该柔性传感器在1 Pa至100 kPa的宽压力范围内具有高灵敏度响应。在小压力下，通过电极与表面微结构之间接触面积的变化实现高灵敏度；在高达100 kPa的高压力下，由于压阻性PDMS/MWCNT材料的多孔结构，传感器保持其高灵敏度。此外，该传感器具有快速响应速度和良好的耐久性。基于多孔微结构PDMS/MWCNT的压阻式压力传感器在声音检测、人体活动监测和空间压力分布阵列映射方面得到了验证。
