Foot activity can reflect numerous physiological abnormalities
in the human body, making gait a valuable metric in health monitoring.
Research on flexible sensors for gait monitoring has focused on high
sensitivity, wide working range, fast response, and low detection
limit, but challenges remain in areas such as elasticity, antibacterial
activity, user-friendliness, and long-term stability. In this study,
we have developed a novel capacitive pressure sensor that offers an
ultralow detection limit of 1 Pa, wide detection ranges from 1 Pa
to 2 MPa, a high sensitivity of 0.091 kPa–1, a fast
response time of 71 ms, and exceptional stability over 6000 cycles.
This sensor not only has the ability of accurately discriminating
mechanical stimuli but also meets the requirements of elasticity,
antibacterial activity, wearable comfort, and long-term stability
for gait monitoring. The fabrication method of a dual dielectric layer
and integrated composite electrode is simple, cost-effective, stable,
and amenable to mass production. Thereinto, the introduction of a
dual dielectric layer, based on an optimized electrospinning network
and micropillar array, has significantly improved the sensitivity,
detection range, elasticity, and antibacterial performance of the
sensor. The integrated flexible electrodes are made by template method
using composite materials of carbon nanotubes (CNTs), two-dimensional
titanium carbide Ti3C2T
x
(MXene), and polydimethylsiloxane (PDMS), offering synergistic
advantages in terms of conductivity, stability, sensitivity, and practicality.
Additionally, we designed a smart insole that integrates the as-prepared
sensors with a miniature instrument as a wearable platform for gait
monitoring and disease warning. The developed sensor and wearable
platform offer a cutting-edge solution for monitoring human activity
and detecting diseases in a noninvasive manner, paving the way for
future wearable devices and personalized healthcare technologies.