Institute of Microelectronics, Tsinghua University, Beijing, China.
Nanoscale. 2016 Dec 8;8(48):20090-20095. doi: 10.1039/c6nr07620c.
Strain sensors have been widely used in the fields of wearable devices, robot arms, medical sensing, bio-sensing, artificial skin and so on, but the existing strain sensors have some shortcomings such as a limited gauge factor (GF) or strain range. We fabricate a novel and flexible strain sensor with high performance based on self-locked overlapping graphene sheets (SOGS) which can be used for wearable devices. Polydimethylsiloxane (PDMS) is used to lock the overlapping graphene sheets, and then the graphene can be stretched and achieve an ultrahigh GF. In addition, a new theory is put forward to explain the GF changes with strain range for the SOGS strain sensor. In this work, graphene oxide (GO) film is reduced to reduced GO (rGO) by a laser. Then, the SOGS and electrodes are encapsulated by PDMS. The SOGS strain sensor has a high GF up to 400 and strain range over 7.5%, and this SOGS strain sensor achieves a balance between high sensitivity and large strain range compared with other existing strain sensors. Furthermore the theoretical equation based on the new theory agrees well with the experimental results. And this strain sensor can be used in many applications because of its high sensitivity. Some applications of the SOGS strain sensors are demonstrated for the detection of various human motions and human sounds. The SOGS strain sensor can exhibit great potential in wearable electronics because of its good balance between high sensitivity and large strain.
应变传感器已广泛应用于可穿戴设备、机械臂、医疗传感、生物传感、人造皮肤等领域，但现有的应变传感器存在一些缺点，如应变系数（GF）有限或应变范围有限。我们基于自锁定重叠石墨烯片（SOGS）制造了一种新型的高性能、灵活的应变传感器，可用于可穿戴设备。聚二甲基硅氧烷（PDMS）用于锁定重叠的石墨烯片，然后可以拉伸石墨烯，实现超高的 GF。此外，提出了一种新的理论来解释 SOGS 应变传感器的 GF 随应变范围的变化。在这项工作中，通过激光将氧化石墨烯（GO）薄膜还原为还原氧化石墨烯（rGO）。然后，用 PDMS 封装 SOGS 和电极。SOGS 应变传感器具有高达 400 的高 GF 和超过 7.5%的应变范围，与其他现有的应变传感器相比，这种 SOGS 应变传感器在高灵敏度和大应变范围之间实现了平衡。此外，基于新理论的理论方程与实验结果吻合较好。由于其高灵敏度，这种应变传感器可以应用于许多应用中。展示了一些用于检测各种人体运动和人体声音的 SOGS 应变传感器的应用。由于其在高灵敏度和大应变之间的良好平衡，SOGS 应变传感器在可穿戴电子产品中具有巨大的潜力。
