Preparation and properties of phase-change materials with enhanced radial thermal conductivities based on anisotropic graphene aerogels

Abstract

In this study, anisotropic graphene aerogels are prepared using the heat-flow method. Then, graphene aerogels with nanosilver particles are prepared via a silver mirror reaction. The aerogels are soaked in paraffin wax and the effects on the properties of the wax are investigated. The thermal conductivity of pure paraffin wax is 0.2553 W m⁻¹ K⁻¹. For the prepared PCM, the aerogel content was 0.92 vol%; this increases to 1.2234 W m⁻¹ K⁻¹, which corresponds to a thermal conductivity enhancement efficiency of 582%. The axial thermal conductivity is 1.4953 W m⁻¹ K⁻¹, which corresponds to a thermal conductivity enhancement efficiency of 746%. The graphene aerogels with the nanosilver particles show high phase-change efficiency. Owing to the significant improvements in the axial and thermal conductivities, the radial and axial heat transfer properties show good consistency suitable for practical applications.