Tunable sign of magnetoresistance in graphene foam – Ecoflex® composite for wearable magnetoelectronic devices

Abstract

Usually, positive magnetoresistance (PMR) is observed in graphene foam (GF) under all temperature and magnetic field range. Herein, large negative magnetoresistance is observed under a temperature range 300–200 K which switches to PMR under a temperature range 200–5 K in graphene foam (GF)-Ecoflex® specimen. The GF-Ecoflex® shows NMR in highly crosslinked specimen, while lightly crosslinked shows PMR at room temperature. This indicates that the sign of magnetoresistance can be controlled by controlling viscoelasticity of Ecoflex® in GF-Ecoflex® specimens, which is very useful for wearable magnetoelectronics.