Joule Heating and mechanical properties of epoxy/graphene based aerogel composite

While polymer composites are anticipated as a promising alternative for Joule heating materials, constructing a continuous conductive network of fillers remains an open challenge to obtain high-performance Joule heating properties with the high steady-state surface temperature at low power input, rapid heating/cooling rate, and excellent cycle stability. Herein, we designed a three-dimensional graphene-based aerogel, infiltrated epoxy into it, and demonstrated a key role of 2D materials-based three-dimensional filler on the anisotropic Joule heating performances of the final aerogel composite. The aerogel composite with the highest graphene loading of 4.7 wt% shows outstanding Joule heating performance with a steady-state temperature of 213 °C at a relatively low applied voltage of 5 V. Benefiting from the 3D graphene structure, the epoxy/graphene-based aerogel composites show an excellent electrical conductivity of 48.7 S/m and thermal conductivity of 1.1 W/mK along the parallel direction to the lamellar structure growth. The Joule heating performance of epoxy/graphene-based aerogel composite is correlated with the morphology, electrical conductivities, and thermal conductivities. Importantly, the induced steady-state temperature follows a linear relationship with both the electrical and thermal conductivities of materials. Mechanical properties of aerogel composite is also studied. The obtained results indicate that the epoxy/graphene-based aerogel composite can be a promising material for thermal management applications.