Embedded large strain sensors with graphene-carbon black-silicone rubber composites

Wearable electronics have generated a strong demand for stretchable, skin-mountable and flexible sensors. This paper provides an effective technique for fabricating conductive networks using graphene-based polymer composites. Graphene-carbon black-silicone rubber (G-CB-SR) composites were cast in a mould, and a film was fabricated to make a composite strain sensor. Here we investigate how the remarkably different geometry affects the effective conductivity and piezoresistive properties of the composites. The electromechanical response of the G-CB-SR composites showed highly reversible and durable behaviour. It was stretchable up to 300%, and the gauge factor (GF) depended on the composition of the composites. The large strain sensors made of high-quality G-CB-SR film was achieved by solution intercalation with low-cost production and easy scalability.