Pan Hong, Xie Guangzhong, Pang Wenqian, Wang Si, Wang Yang, Jiang Zhi, Du Xiaosong, Tai Huiling
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, PR China.
Electrical and Electronic Engineering and Information Systems, The University of Tokyo, 113-8656 Tokyo, Japan.
ACS Appl Mater Interfaces. 2020 Aug 26;12(34):38805-38812. doi: 10.1021/acsami.0c11658. Epub 2020 Aug 13.
Polypyrrole (PPy) is a good candidate material for piezoresistive pressure sensors owing to its excellent electrical conductivity and good biocompatibility. However, it remains challenging to fabricate PPy-based flexible piezoresistive pressure sensors with high sensitivity because of the intrinsic rigidity and brittleness of the film composed of dense PPy particles. Here, a rational structure, that is, 3D-conductive and elastic topological film composed of coaxial nanofiber networks, is reported to dramatically improve the sensitivity of flexible PPy-based sensors. The film is prepared through surface modification of electrospun polyvinylidene fluoride (PVDF) nanofibers by polydopamine (PDA), in order to homogeneously deposit PPy particles on the nanofiber networks with strong interfacial adhesion (PVDF/PDA/PPy, PPP). This unique structure has a high surface area and abundant contact sites, leading to superb sensitivity against a subtle pressure. The as-developed piezoresistive pressure sensor delivers a low limit of detection (0.9 Pa), high sensitivity (139.9 kPa), fast response (22 ms), good cycling stability (over 10,000 cycles), and reliability, thereby showing a promising value for applications in the fields of health monitoring and artificial intelligence.
聚吡咯（PPy）因其优异的导电性和良好的生物相容性，是压阻式压力传感器的理想候选材料。然而，由于由致密PPy颗粒组成的薄膜具有固有的刚性和脆性，制造具有高灵敏度的基于PPy的柔性压阻式压力传感器仍然具有挑战性。在此，据报道一种合理的结构，即由同轴纳米纤维网络组成的三维导电且弹性的拓扑薄膜，可显著提高基于PPy的柔性传感器的灵敏度。该薄膜是通过用聚多巴胺（PDA）对静电纺丝聚偏氟乙烯（PVDF）纳米纤维进行表面改性来制备的，以便将PPy颗粒均匀地沉积在具有强界面粘附力的纳米纤维网络上（PVDF/PDA/PPy，PPP）。这种独特的结构具有高表面积和丰富的接触位点，从而对细微压力具有卓越的灵敏度。所开发的压阻式压力传感器具有低检测限（0.9 Pa）、高灵敏度（139.9 kPa）、快速响应（22 ms）、良好的循环稳定性（超过10,000次循环）和可靠性，因此在健康监测和人工智能领域的应用中显示出有前景的价值。
