Oh Seungwoo, Kim Jin, Chang Suk Tai
School of Chemical Engineering and Materials Science, Chung-Ang University 84 Heukseok-ro, Dongjak-gu Seoul 06974 Republic of Korea
RSC Adv. 2018 Dec 18;8(73):42153-42159. doi: 10.1039/c8ra08721k. eCollection 2018 Dec 12.
Strain sensor technologies have been spotlighted for their versatility for healthcare, soft robot, and human-robot applications. Expecting large future demands for such technology, extensive studies have investigated flexible and stretchable strain sensors based on various nanomaterials and metal films. However, it is still challenging to simultaneously satisfy parameters such as sensitivity, stretchability, linearity, hysteresis, and mass producibility. In this work, we demonstrate a novel approach for producing highly sensitive metal-grid strain sensors based on an all-solution process, which is suitable for mass production. We investigated the effects of the width of the metal grid and width/spacing ratio on the piezoresistivity of the strain sensors. The metal grid strain sensors exhibited high sensitivity (gauge factor of 4685.9 at 5% strain), rapid response time (∼18.6 ms), and superior strain range (≤5%) compared to other metal-based sensors. We demonstrated that the sensors could successfully convert voice signals and tiny movements of fingers and muscles into electrical signals. In addition, the metal-grid strain sensors were produced using a low-cost procedure without toxic solvent an all water-based solution process, which is expected to allow the integration of such metal-grid strain sensors into future highly sensitive physical sensing devices.
应变传感器技术因其在医疗保健、软体机器人和人机交互应用中的多功能性而备受关注。鉴于未来对此类技术的巨大需求，大量研究已对基于各种纳米材料和金属薄膜的柔性可拉伸应变传感器展开了调查。然而，要同时满足灵敏度、可拉伸性、线性度、滞后性和大规模生产能力等参数仍具有挑战性。在这项工作中，我们展示了一种基于全溶液工艺生产高灵敏度金属网格应变传感器的新方法，该方法适用于大规模生产。我们研究了金属网格宽度和宽度/间距比对应变传感器压阻特性的影响。与其他金属基传感器相比，金属网格应变传感器表现出高灵敏度（在5%应变下的应变系数为4685.9）、快速响应时间（约18.6毫秒）和优异的应变范围（≤5%）。我们证明了这些传感器能够成功地将语音信号以及手指和肌肉的微小运动转换为电信号。此外，金属网格应变传感器采用低成本工艺生产，且不使用有毒溶剂——一种全水性溶液工艺，有望将此类金属网格应变传感器集成到未来的高灵敏度物理传感设备中。
