Conductive/non-conductive bi-compartmental architectures for sensing applications†

Bi-compartmental microscopic structure of a material provides an opportunity to tune its functions by integrating together different properties. The bi-compartmental materials with a conductive part on one side and a non-conductive part on the other side were created with microfluidic technology (MF), in which the rate of change of resistance depends on the ratio of the two compartments. A series of bi-compartmental particles with tunable resistance were prepared with different flow ratios of the two dispersed phases (i.e., V_EG-AN). The downtrend of the resistance–pressure plot is decided by the ratio of the conductive compartment. Similarly, bilateral fibres with different ratios of the conductive part were fabricated with MF, with the cross-section consisting of two distinctively different compartments. The downtrend of resistance–pressure plots depends on the ratio of the conductive part in bilateral fibres (i.e., V_AU). The final relative resistance variation (i.e., ΔR/R₀) increases with the improving ratios of the conductive part, which is more than 95% for bi-compartmental particles with V_EG-AN at 40% and exceeds 99% for all bilateral fibres. A sensing mechanism of contact resistance is proposed with a deduced mathematical model for perfectly explaining the plots of electric resistance versus pressure. Furthermore, soft fibre sensors were woven with bilateral fibres for monitoring pressure, finger posture and breath.