Highly Sensitive and Stable Wearable Pressure Sensors Based on a Self-Assembled Nanofibrous Elastic Microcube Array

Wearable sensors can solve the problems of traditional detection equipment like limited portability, considerable size, and high production cost. These sensors have greatly propelled the development of wearable electronic devices, which can be used in the fields of human–machine interfacing, medical care, and automatic emergency systems. In order to improve the sensitivity of wearable sensors, we presented a facile and effective strategy to construct an asymmetric structure polyurethane/fluorinated polyurethane (PU/FPU) nanofibrous dielectric layer with a self-assembled microcube array via template collector-assisted electrospinning, develop efficient conductive Nomex/silver (Ag)/FPU nanofibrous electrodes, and finally assemble two electrode layers and one dielectric layer to obtain a wearable capacitive pressure sensor. The PU/FPU dielectric layer demonstrated outstanding deformation responsiveness when subjected to external force and achieved satisfactory recoverability, and the obtained Nomex/Ag/FPU nanofibrous electrode showed good electrical conductivity with a connected Ag network. The obtained sensors displayed high sensitivity to pressure because of the localized stress concentration generated by the microcube array, and the sensor exhibited a wide pressure range (0–20 kPa) and high sensitivity (0.093 kPa–1 at 0–1 kPa, 0.069 kPa–1 at 5–20 kPa). Consequently, these sensors were capable of monitoring tiny pressure changes and detecting human actions. They contribute to the development of capacitive pressure sensors that have a linear ΔC/C0 response and excellent reproducibility, which are suitable for individual healthcare and advanced human–computer interface systems.