Graphene-PVDF aerogel composites for humidity sensing applications

Optimal humidity levels are vital for human health, impacting respiratory comfort, skin hydration, and susceptibility to respiratory issues. Hence, the development of precise humidity sensors is crucial for monitoring indoor environments, ensuring healthy humidity levels, and ultimately enhancing well-being. A novel method for producing three-dimensional (3D) porous composite materials utilizing graphene is described, incorporating two consecutive steps. Initially, a homogeneous solution of GNP/PVDF is prepared to ensure even dispersion through the solution-mixing process, followed by bulk formation in the second step, which is then freeze-dried to produce aerogel. The produced aerogel exhibits a reasonable relative resistance change of 40% at high humidity (94%RH), with response and recovery time of 20s and 160s, respectively, which is important in human respiration monitoring. The porous humidity sensor also successfully detects human respiratory patterns with normal breathing rates.