Controllable synthesis of 3D-BN hollow nanonets for thermal-conductive epoxy composites

Abstract

With the advancement of modern electronic equipment toward miniaturization, high integration, and intelligence, a large amount of heat is being generated during operation. Consequently, there is a higher demand for efficient heat dissipation from thermal management materials (TMMs). In this study, three-dimensional boron nitride hollow nanonets (3D-BNHNs) were fabricated using strontium borate nanonets as templates. The effect of synthesis conditions on the morphology of 3D-BNHNs was studied. Based on the findings, potential chemical reactions and growth mechanisms were proposed to elucidate the formation of 3D-BNHNs. At a low load of 3 wt%, the tensile strength of the composite was 54.88 MPa, 46.35% higher than that of pure epoxy resin (EP). The through-plane and in-plane thermal conductivities of the 3 wt% 3D-BNHNs/EP composite reached 0.336 W·m-1·K-1 and 1.812 W·m-1·K-1, respectively, corresponding to enhancements of 86.67% and 906.67% over pure EP. The composite also demonstrated excellent thermal conductivity enhancement efficiency, with an in-plane rate as high as 302.22% and a through-plane rate of 28.89%. This improvement is attributed to 3D-BNHNs establishing an efficient thermal conduction network within the EP matrix. Moreover, the composites exhibited excellent electrical insulation and thermal stability. This study provides novel insights into the development of high-thermal-conductivity packaging insulation materials, paving the way for advanced thermal-management solutions in next-generation electronic devices.