Highly thermally conductive SiO2-coated NFC/BNNS hybrid films with water resistance

The miniaturization, integration, and lightweight of modern electronics have posed serious challenges to the development of high-performance and multifunctional thermal management materials. Here, we reported SiO2 coated nanofibrillated cellulose (NFC)/boron nitride nanosheets (BNNS) hybrid films with excellent thermal conductivity (TC) and hydrophobicity. These films were easily constructed via vacuum-assisted filtration and subsequent hydrophobic coating. The hybrid films exhibit a well-defined aligned structure with in-plane oriented BNNS. This finding was proven via wide-angle and small-angle X-ray scattering techniques, allowing for a high TC of up to 10.88 W m(-1) K-1 at a low BNNS content of 7 wt%. Moreover, the hydrophobic hybrid films achieve high tensile strength (166.47 MPa) and electrical insulating property (volume resistivity = 1.2 x 10(12) Omega cm). Inspired by the lotus effect, the water contact angle of such hydrophobic hybrid films reaches 143 degrees, showing great potential in real applications for preventing the adverse effects of water and moisture.

Automated summary

SiO2 coated NFC/BNNS hybrid films with excellent thermal conductivity and hydrophobicity were reported. These films exhibit high tensile strength and electrical insulating properties, with a water contact angle of 143 degrees, showing great potential for practical applications.