A Stretchable Graphene Thin-Film Sensor for Detecting All of Lateral and Vertical Strains

In this work, we propose a stretchable graphene film sensor that can detect all of lateral and vertical strain with unique architecture in single sensor element since most approaches so far are only available for detecting either lateral or vertical strain, but not both. The sensor is fabricated with percolative networks of graphene nanoplatelet using spray-coating method for constructing strain sensing channel and electrode simultaneously. The sensor exhibits a high stretchability of 150% with a gauge factor of 8.56 (0-100%) and 19.8 (100-150%) in the two regimes, for lateral strain. The sensor also presents a high sensitivity ((ΔR/R₀)/ΔP of -0.026 kPa^-1) for vertically applied pressure in the range of 100-20,000 Pa, belonging to general human pressure perception range. Based on the sensing properties demonstrated, the proposed graphene sensor is a promising candidate for sensor that can detect both lateral and vertical strains in single sensor element.