A CNT- and ZnO nanorod-incorporated fish gelatin nanocomposite towards developing flexible pressure/strain sensors for human motion monitoring

Abstract

A comprehensive analysis of a novel nanocomposite, namely, FGCZ nanocomposite that is composed of fish gelatin (FG), carbon nanotubes (CNTs), and zinc oxide nanorods (ZNRs), was carried out for its potential use in pressure/strain sensing applications. High-resolution transmission electron microscopy confirmed a well-graphitized multi-walled structure with minimal defects in the CNTs while highlighting the polycrystalline nature of the ZNRs. The nanofillers were uniformly dispersed within the polymer matrix, resulting in enhanced Young's modulus and ultimate tensile strength by 350% and 250%, respectively, driven by the strong interfacial interactions between the CNTs, ZNRs, and FG. Electrical conductivity increased (up to ∼11 000 times) with increasing nanofiller concentrations owing to the formation of conductive networks, although agglomeration at higher concentrations (0.30 wt%) impeded the performance. The FGCZ nanocomposite containing 0.25 wt% nanofillers demonstrated excellent electrical properties, making it an ideal candidate for further exploration of its pressure/strain sensing capabilities. The FGCZ nanocomposite exhibited sensing abilities, which can be attributed to the formation of efficient conductive pathways under mechanical deformation. Moreover, the nanocomposite demonstrated rapid biodegradability, fully degrading in water within 30 min, highlighting its potential as an environmentally sustainable material.