Flexible, self-powered, miniaturized, ultrasensitive flow sensors are in high demand for human motion detection, myoelectric prosthesis, biomedical robots, and health-monitoring devices. This paper reports a biomimetic nanoelectromechanical system (NEMS) flow sensor featuring a PVDF nanofiber sensing membrane with a hydrogel infused, vertically aligned carbon nanotube (VACNT) bundle that mechanically interacts with the flow. The hydrogel-VACNT structure mimics the cupula structure in biological flow sensors and gives the NEMS flow sensor ultrahigh sensitivity via a material-induced drag force enhancement mechanism. Through hydrodynamic experimental flow characterization, this work investigates the contributions of the mechanical and structural properties of the hydrogel in offering a sensing performance superior to that of conventional sensors. The ultrahigh sensitivity of the developed sensor enabled the detection of minute flows generated during human motion and micro-droplet propagation. The novel fabrication strategies and combination of materials used in the biomimetic NEMS sensor fabrication may guide the development of several wearable, flexible, and self-powered nanosensors in the future.

对于人体运动检测，肌电假体，生物医学机器人和健康监测设备，对灵活，自供电，小型化，超灵敏的流量传感器提出了很高的要求。本文报道了一种仿生纳米机电系统（NEMS）流量传感器，该传感器具有PVDF纳米纤维感测膜和水凝胶注入的垂直排列的碳纳米管（VACNT）束，该束与流机械相互作用。水凝胶-VACNT结构模仿生物流量传感器中的吸盘结构，并通过材料诱导的阻力增强机制使NEMS流量传感器具有超高的灵敏度。通过流体动力学实验流量表征，这项工作研究了水凝胶的机械和结构特性在提供优于常规传感器的传感性能方面的贡献。先进的传感器具有超高的灵敏度，可以检测人体运动和微滴传播过程中产生的微小流量。仿生NEMS传感器制造中使用的新颖制造策略和材料组合可能会指导未来几种可穿戴，柔性和自供电纳米传感器的开发。