Fabrication of silver nanoparticles/copper nanoparticles jointly decorated nitride flakes to improve the thermal conductivity of polymer composites

In this research project, the hexagonal boron nitride@(silver/copper) (h-BN@(Ag/Cu)) hybrids are successfully synthesized through a jointly decorated two-step process in this work. First, the copper nanoparticles (CuNPs) are decorated on h-BN flakes by reducing copper ions (Cu2+). Subsequently, h-BN@(Ag/Cu) hybrids are fabricated via silver nanoparticles (AgNPs) deposition on the surface of hexagonal boron nitride@copper (h-BN@Cu) flakes. The obtained h-BN@(Ag/Cu) hybrids serve as loading fillers to substantially boost the thermal conductivity of poly(dimethylsiloxane) (PDMS). The thermal conductivity of as-prepared h-BN@(Ag/Cu)/PDMS composite reaches 1.5645 W m(-1 )K(-1) at 25 vol% filler loading. Furthermore, the electrical properties of these composites are comprehensively investigated. Additionally, the mechanism of h-BN@(Ag/Cu) hybrids for thermal conductivity improvement are demonstrated utilizing Fogg's model. This work may provide valuable insight and information for the design and construction of high-performance thermally conductive materials in the future.