Investigation of cost-effective carbon nanofiber/carbon fiber and silicone polymer composite material for wearable bioimpedance device

Wearable health monitoring devices have gained more popularity in recent years, but there are still many challenges that need to be solved. Sensors and electrodes that these devices are using are often uncomfortable and not suitable for long-time measurements. This paper investigates carbon nanofiber/carbon fiber and silicone composite material that could be employed as electrodes to register bioimpedance change in the wrist area. Flexible, low-cost and electrically conductive sensors, showed good linear strain sensitivity response when stretched to 100%, but the gauge factor was fairly low (~0.7). Also, investigating impedance change of the composite under compressive loading/unloading presented regular and continuous downward shift suggesting instability. We demonstrate the potential application of fabricated material as electrodes by registering bioimpedance change and comparing it with widely used Ag/AgCl electrodes. Prepared carbon nanofiber and silicone mixture showed promising results as an electrode for wearable device.