Effect of Particle Size on Viscoelastic and Electrical Properties of Reduced Graphene Oxide Films

Abstract

Structural materials with high damping and stiffness can reduce the weight of structures in several applications, yet they do not exist yet. Films made from 2D materials such as graphene have the potential to realize this new set of material properties. This study investigates the impact of particle size on the viscoelastic and electrical properties of graphene oxide (GO) and reduced graphene oxide (rGO) films. Two types of GO films were fabricated, one using small GO sheets and the other using large GO sheets. The size difference was confirmed through electron microscopy, revealing an average lateral size of approximately 1 μm for small particles and 9 μm for large particles. Particle packing differs for the tested samples and is correlated to their storage modulus and damping. Similarly, the electrical conductivities of the reduced films are measured and explained in terms of particle size, functional groups, and packing. This study reveals the processing-structure-property relationships in GO/rGO films, a crucial step in realizing their potential for achieving simultaneous high stiffness and damping for noise, vibration, and impact damage mitigation.