Highly thermally conductive multifunctional graphene-based composite membrane for remarkable passive heat dissipation and robust superhydrophobicity

Abstract

Graphene membrane is considered the preferred item of thermal conductivity material for wearable devices due to its unique flexibility and high thermal conductivity. However, water condensation beads are easily generated on the surface of graphene membranes under high heat and humidity operating conditions. Water condensation beads not only reduce the thermal conductivity of the membrane but may also cause damage to electronic components. To address this issue, an anti-liquid film condensation function can be obtained by spraying an alumina/multi-walled carbon nanotubes/thermoplastic elastomer composite powder (Al2O3/MWCNTs/SEBS) modified by 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (POTS) on graphene membranes. In addition, the obtained composite films have high thermal conductivity (up to 483.1 W/m·K), good superhydrophobicity and antifouling properties, and stable physicochemical properties. The hydrophobicity angle could reach 166 ± 3.3° and the rolling angle 7 ± 2.4°. Under 300 times of bending, it can still maintain its superhydrophobic performance. Therefore, the development of graphene-based composite membrane with high thermal conductivity, hydrophobicity and an excellent water-resistant condensation bead effect is expected to provide a new thermally conductive material solution for heat dissipation in electronic components.