Although flexible sensors have attracted
considerable attention
in emerging fields, including wearable electronics and soft robotics,
their stability must be considered in practical applications, especially
the effects of external factors on the sensing performance. Herein,
a recyclable flexible sensor with superhydrophobicity and a highly
sensitive strain response was developed by combining electrospinning
and ultrasonication anchoring techniques. The constructed hierarchical
network structure is composed of the fluorine-free superhydrophobic
multiwalled carbon nanotubes and a porous elastomer membrane substrate
reinforced by nanoparticles. The obtained sensor exhibited exceptional
strain-sensing performance in terms of ultrahigh sensitivity (maximum
gauge factor of 12 172.46), a fast response time of 80 ms,
and excellent durability (10 000 cycles). Based on these outstanding
merits, the strain sensor can detect various human motions without
being interfered with by harsh environments. Moreover, superhydrophobic
membranes can be combined with electronic devices for weather monitoring
and underwater sensing. Noteworthily, damaged sensors can be quickly
dissolved by a small amount of cyclohexane, enabling material recovery.
The recyclable multifunctional membranes could reduce the potential
pollution to the environment and show highly promising applications
in complex environments.