All-Fabric Ultrathin Capacitive Sensor with High Pressure Sensitivity and Broad Detection Range for Electronic Skin

ACS Appl Mater Interfaces. 2021 May 26;13(20):24062-24069. doi: 10.1021/acsami.1c05478. Epub 2021 May 12.

Abstract

Flexible pressure sensors have emerged as an indispensable part of wearable devices due to their application in physiological activity monitoring. To realize long-term on-body service, they are increasingly required for properties of conformability, air permeability, and durability. However, the enhancement of sensitivity remains a challenge for ultrathin capacitive sensors, particularly in the low-pressure region. Here, we introduced a highly sensitive and ultrathin capacitive pressure sensor based on a breathable all-fabric network with a micropatterned nanofiber dielectric layer, an all-fabric capacitive sensor (AFCS). This all-fabric network endows a series of exceptional performances, such as high sensitivity (8.31 kPa-1 under 1 kPa), ultralow detection limit (0.5 Pa), wide detection range (0.5 Pa to 80 kPa), and excellent robustness (10 000 dynamic cycles). Besides, the all-fabric structure provides other properties for the AFCS, e.g., high skin conformability, super thinness (dozens of micrometers), and exceptional air permeability. Our AFCS shows promising potential in breathing track, muscle activity detection, fingertip pressure monitoring, and spatial pressure distribution, paving way for comfortable skinlike epidermal electronics.

Keywords: all-fabric structure; capacitive effect; flexible ultrathin sensors; high sensitivity.

MeSH terms

  • Electric Capacitance
  • Equipment Design
  • Humans
  • Monitoring, Physiologic / instrumentation*
  • Nanofibers / chemistry*
  • Sensitivity and Specificity
  • Wearable Electronic Devices*