Mimicking swallow nest structure to construct 3D rGO/BN skeleton for enhancing the thermal conductivity of the silicone rubber composites

Ever-increasing heat flux density in electronic systems has posed significant challenges to their efficient thermal management, and therefore, there is an urgent need for high-performance thermal management materials. However, conventional heat-conducting rubber composites require extremely high filler loadings to achieve high thermal conductivities, which may compromise mechanical properties, flexibility, and cost. Herein, we take inspiration from the structure of the swallow nest and successfully construct a 3D continuous skeleton with reduced graphene oxide (rGO) sheets and boron nitride (BN) plates. This 3D rGO/BN skeleton is modeled on air bubbles and has a porous structure similar to a swallow nest, endowing the silicone rubber composite with excellent thermal conductivity. The resulting 3D T-rGO/BN/PDMS composites exhibited significantly enhanced thermal conductivity (up to 1.41 W/mK) at low filler loadings (14.3 vol%). Model fitting analysis and finite element simulations deeply revealed the mechanisms behind the superior thermal conductive performance of the composites. This strategy provides valuable guidance for low-cost, large-scale preparation of heat-conducting rubber composites, which is expected to be applied to heat dissipation of emerging electronic devices.