3 research outputs found
Ultrasensitive mechanical crack-based sensor inspired by the spider sensory system
Recently developed flexible mechanosensors based on inorganic
silicon1–3, organic semiconductors4–6, carbon nanotubes7, graphene
platelets8, pressure-sensitive rubber9 and self-powered devices10,11 are
highly sensitive and can be applied to humanskin.However, the development
of amultifunctional sensor satisfyingthe requirementsofultrahighmechanosensitivity,
flexibility and durability remains a challenge.
In nature, spiders sense extremely small variations inmechanical stress
using crack-shaped slit organs near their leg joints12.Herewedemonstrate
that sensors based on nanoscale crack junctions and inspired by
the geometry of a spider’s slit organ can attain ultrahigh sensitivity
and servemultiple purposes. The sensors are sensitive to strain (with
agaugefactorofover 2,000inthe0–2percentstrainrange)andvibration
(withthe ability todetectamplitudes of approximately 10 nanometres).
The device is reversible, reproducible, durable andmechanically flexible,
and can thus be easily mounted on human skin as an electronic
multipixel array.Theultrahigh mechanosensitivity is attributed to the
disconnection–reconnection process undergone by the zip-like nanoscale
crack junctionsunder strain or vibration.Theproposedtheoretical
model is consistent with experimental data that we report here. We
also demonstrate that sensors based on nanoscale crack junctions
are applicable to highly selective speech pattern recognition and the
detection of physiological signals. The nanoscale crack junction-based
sensory system could be useful in diverse applications requiring ultrahigh
displacement sensitivity.12462661sciescopu