Ying Chen1,Qiran Cai1,Hongbo Jiang1,Srikanth Mateti1,Elton Santos2,Luhua Li1
Deakin University1,The University of Edinburgh2
Ying Chen1,Qiran Cai1,Hongbo Jiang1,Srikanth Mateti1,Elton Santos2,Luhua Li1
Deakin University1,The University of Edinburgh2
Heat dissipation becomes increasingly critical, especially in miniaturised modern devices, and boron nitride (BN) nanosheets are considered as a promising material for heat dissipation because of high thermal conductivity yet electrical insulation. Here, we firstly report the intrinsic thermal conductivity of atomically thin BN, and the density functional theory calculation reveals the thickness and isotope effects on the heat transport <i>(1-2)</i>. To improve the dispersibility of BN nanosheets for the fabrication of advanced composites, we develop a simple, yet efficient mechanochemical exfoliation technique to prepare functionalised BN nanosheets with excellent dispersibility in water and organic solvents <i>(3)</i>. Using the high-quality BN nanosheet dispersion as a precursor, BN spheres with high, isotropic thermal conductivity are fabricated, which can isotropically enhance the thermal conductivity of poly(vinyl alcohol) by ~3700%, and address the challenge that BN reinforced polymer offers a highly anisotropic thermal conductivity <i>(4)</i>. This study provides not only the important insight into the heat transport and phonon scattering mechanism, but also a practical route to fabricate BN-enhanced thermal interface materials with high isotropic thermal conductivity and promising materials that are valuable for heat dissipation in new-era advanced electronics and related applications.<br/><b>Reference</b><br/>(1) Q Cai, D Scullion, W Gan, A Falin, S Zhang, K Watanabe, T Taniguchi, Y Chen, E J G Santos, L H Li, <i>Science Advances</i>, 5, <b>2019</b>, eaav0129.<br/>(2) Q Cai, D Scullion, W Gan, A Falin, P Cizek, S Liu, J H Edgar, R Liu, B C C Cowie, E J G Santos, L H Li, <i>Phys. Rev. Lett.</i>, 125, <b>2020</b>, 085902.<br/>(3) H Jiang, Q Cai, S Mateti, Y Yu, C Zhi, Y Chen, <i>ACS Applied Materials & Interfaces,</i> 13, <b>2021</b>, 44751-44759.<br/>(4) H Jiang, S Mateti, Q Cai, H Shao, S Huang, Z-S Wu, C Zhi, Y I Chen, <i>Composite Science and Technology</i>, 230, <b>2022</b>, 109769.