Graphene/epoxy coating with radiation heat dissipation properties for spacecraft thermal management

Abstract

In the space environment, the heat dissipation of spacecraft primarily relies on thermal radiation. To reduce the weight of spacecraft, it is necessary to replace the existing copper radiators with aluminum ones. However, aluminum radiators have a lower emissivity, which results in suboptimal heat dissipation performance. Therefore, enhancing the emissivity of aluminum radiators is crucial for improving their heat dissipation performance. This study investigates the rapid (100 s) reduction of graphene oxide (GO) into low-defect reduced graphene oxide (mRGO) using Joule heating for 100 s, followed by non-covalent modification to further enhance its dispersion in water. By incorporating modified reduced graphene oxide (mRGO) as the primary filler in an aqueous epoxy resin emulsion and using 3-aminopropyltriethoxysilane (APTES) to enhance the adhesion between the coating and the aluminum substrate, a composite Graphene/Epoxy radiation heat dissipation coating (GERC) with high emissivity and strong adhesion was successfully prepared. Experimental results demonstrate that the coating containing 4 wt% mRGO filler exhibits the optimal heat dissipation efficiency (24.15%) and significantly enhances the infrared emissivity of the substrate (up to 0.93). This coating exhibits excellent thermal stability and strong adhesion, providing a novel approach for thermal management in space radiators.