Large-Area Carbon Nanotube-Based Flexible Composites for Ultra-Wide Range Pressure Sensing and Spatial Pressure Mapping
Large-Area Carbon Nanotube-Based Flexible Composites for Ultra-Wide Range Pressure Sensing and Spatial Pressure Mapping
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DOI：
10.1021/acsami.9b17100
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发表时间：
2019-12-25
影响因子：
9.5
通讯作者：
Thostenson, Erik T.
中科院分区：
文献类型：
--
作者：
Dai, Hongbo;Thostenson, Erik T.
柔性压力传感器对于包括人机接口、可穿戴电子设备和物体/运动检测的应用具有广泛的兴趣。然而，与组成材料，制造工艺，传感机制和硬接线相关的复杂性往往阻碍了文献中报道的使用高性能压力传感器的大规模应用。在这里，我们展示了一个大面积的，高度灵活的，顺应性，和机械鲁棒性的压力传感器，使用硅橡胶弹性体与嵌入式非织造织物载体涂有碳纳米管。所选的有机硅聚合物允许传感器的全厚度变形性，而高模量织物载体确保面内刚度和稳定性。该传感器的初始电导率为4.4 +/- 0.38 S/m，采用简单的浸涂和聚合物注入工艺制造，可以很容易地扩大规模，用于大规模应用。基于其分层复合结构，该压阻式压力传感器具有极高的压缩弹性、可重复的单调正压力相关性以及可分段线性化的超宽弹性工作范围（5.5 +/- 0.5 MPa）。一个真正的二维模式的空间压力映射是通过利用电阻抗断层扫描（EIT）实现的，并证明产生电导率图，可以估计的位置，形状和幅度的局部和分布的压力与简单的接触面积。
Flexible pressure sensors are of broad interest for applications including human-machine interfaces, wearable electronics, and object/motion detection. However, complexities associated with constituent materials, fabrication processes, sensing mechanisms, and hardwiring often hinder the large-scale applications of using high performance pressure sensors reported in the literature. Here we demonstrate a large-area, highly flexible, conformable, and mechanically robust pressure sensor using a silicone elastomer with an embedded nonwoven textile carrier coated with carbon nanotubes. The selected silicone polymer allows through-thickness deformability of the sensor while the high modulus textile carrier ensures in-plane stiffness and stability. The sensor has an initial electrical conductivity of 4.4 +/- 0.38 S/m and is fabricated using a straightforward dip coating and polymer infusion process and can be easily scaled-up for large-scale applications. On the basis of its hierarchical composite structure, this piezoresistive pressure sensor possesses extremely high resilience under compression, a repeatable monotonic positive pressure correlation, and an ultrawide elastic working range (5.5 +/- 0.5 MPa) that can be segmentally linearized. A true two-dimensional modality for spatial pressure mapping is realized by utilizing electrical impedance tomography (EIT) and demonstrated to yield conductivity maps that can estimate the location, shape, and amplitude of both localized and distributed pressure with simple contact areas.