高灵敏度和高线性度的可拉伸应变传感器的分层结构设计

Hierarchical structural design towards stretchable strain sensors with ultra-high sensitivity and linearity

对柔性电子设备日益增长的需求使得开发具有高灵敏度和高线性度的传感器更加迫切.由于拉伸应变下不可逆结构损伤诱导电阻线性急剧增加,现有的可拉伸应变传感器难以完美地同时实现这两个特性.针对这一问题,本文提出了一种兼具表面褶皱和体相梯度孔隙的新型分级互连结构,利用水热活化机制精确控制纳米级褶皱间距,通过调控相分离中热力学和动力学行为构筑出体相梯度多孔结构,通过改变器件两侧曲率实现各向异性特征,深入研究各种设计的功效、量化几何结构对灵敏度的有效贡献和追踪形态演变.基于器件显著的灵敏度和各向异性,所制备的传感器能够有效监测静态和动态位移、表面运动、二维应变信号变化以及预测液位随时间变化.本工作为实现高质量的感知能力提供了一种广泛适用、适应性强、可扩展且具有成本效益的方法.

The increasing demands for flexible electronic devices have necessitated the development of sensors that possess remarkable sensitivity and linearity.However,conventional strain sensors encounter difficulties in simultaneously achieving above two desired characteristics,because a linear steep increase in resistance is difficult to realize due to the irreversible structural damage under tensile strain.Herein,a novel hierarchical interconnected structure with the external surface wrinkles and internal gradient pores was proposed to achieve extraordinary levels of sensitivity and high linearity in stretchable strain sensors.The nanoscale wrinkle spacing can be precisely controlled by hydrothermal activation mechanism.The bulk gradient porous structure was constructed through the manipulation of thermodynamic and kinetic behaviors of phase separation.Additionally,macroscopic curvatures on both sides of sensors were manipulated to achieve the anisotropy.The efficacy of various designs,quantized effective contributions of geometric configurations on the sensitivity and morphology evolution were discussed in depth.Due to the extraordinary sensitivity and anisotropy,our sensors have the capability to efficiently monitor alterations in both static and dynamic displacement,surface movement and two-dimensional strain signals,as well as predict variations in liquid level over time.Our approach provides a widely applicable,adaptable,scalable,and cost-effective method for achieving high-quality sensing capabilities.