Highly
conductive carbonaceous nanomaterials derived from biomass
fibers (e.g., loofah) have been extensively employed in flexible sensors.
Nonetheless, the even texture of the carbonized loofah (CL) constrained
the contact surface area with adjacent fibers, given its conductivity.
Herein, the CL interlocked by the reduced graphene oxide (rGO) nanosheets
was employed to construct highly conductive hydrogel, which served
as the sensor module and triboelectric nanogenerator (TENG) module
in a self-powered sensing system. Originating from the π–π
interaction, the rGO can be firmly fixed on the surface of CL and
act as a bridge to reduce the electron transfer gap, thereby resulting
in accelerated electron transport. Compared to pristine CL hydrogel,
the electrical conductivity of CL@rGO hydrogel was improved from 28.5
S/m to 55.2 S/m and exhibits improved performance in terms of electrical
output when incorporated into TENG and sensor devices. The built-up
CL@rGO sensor exhibited remarkable durability for more than 10,000
cycles, maximum gauge factor (GF) of 16021 and rapid response time
of 20 ms. Due to these attributes, the sensor is capable of efficiently
monitoring the capacity for complex human activities. CL@rGO exhibits
considerable potential across multiple domains, encompassing wearable
electronics, artificial intelligence devices and human-machine interaction,
owing to its adaptable characteristics.