Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Small. 2019 Aug;15(33):e1901744. doi: 10.1002/smll.201901744. Epub 2019 Jun 13.
Sensor-to-sensor variability and high hysteresis of composite-based piezoresistive pressure sensors are two critical issues that need to be solved to enable their practical applicability. In this work, a piezoresistive pressure sensor composed of an elastomer template with uniformly sized and arranged pores, and a chemically grafted conductive polymer film on the surface of the pores is presented. Compared to sensors composed of randomly sized pores, which had a coefficient of variation (CV) in relative resistance change of 69.65%, our sensors exhibit much higher uniformity with a CV of 2.43%. This result is corroborated with finite element simulation, which confirms that with increasing pore size variability, the variability in sensor characteristics also increases. Furthermore, our devices exhibit negligible hysteresis (degree of hysteresis: 2%), owing to the strong chemical bonding between the conductive polymer and the elastomer template, which prevents their relative sliding and displacement, and the porosity of the elastomer that enhances elastic behavior. Such features of the sensor render it highly feasible for various practical applications in the near future.
基于复合结构的压阻式压力传感器存在传感器间变异性大和滞后现象严重这两个亟待解决的关键问题，这限制了其实际应用。在这项工作中，我们提出了一种压阻式压力传感器，它由具有均匀尺寸和排列孔的弹性体模板以及孔表面上的化学接枝的导电聚合物膜组成。与由随机尺寸孔组成的传感器相比，其相对电阻变化的变异系数（CV）为 69.65%，我们的传感器具有更高的均匀性，CV 为 2.43%。这一结果得到了有限元模拟的证实，模拟结果表明，随着孔径变异性的增加，传感器特性的变异性也随之增加。此外，由于导电聚合物与弹性体模板之间存在较强的化学键，防止了它们的相对滑动和位移，同时弹性体的多孔性增强了弹性行为，因此我们的器件具有可以忽略不计的滞后现象（滞后度为 2%）。传感器的这些特性使其在不久的将来非常适用于各种实际应用。
