Lightweight and Flexible Heat Sink from Carbon Nanotube Sheet

FSU researchers created a lightweight and flexible heat sink based on carbon nanotube (CNT) sheet which can also be expanded to other lightweight sheets such as graphene and boron nitride free-standing sheets. CNTs have good electrical and thermal conductivity with large surface to volume ratio due to its nanostructures and these properties are good for heat dissipation. Compared to the conventional aluminum heat sink or copper heat pipes, CNT sheets are more lightweight and have more flexibility; this reduces the manufacturing cost and makes it possible for versatile application with easier shape deformations.

Different CNTs can be used for free-standing sheet fabrication either multi-walled CNT and/or double-walled CNT. Entangled CNT structures show voids and large surface area and this also increase the convective heat dissipation in addition to the thermal conduction. Also the novel heat sink design has increased surface area to enhance the convective heat dissipation and flexible CNT sheet can increase the design freedom of the heat sink with higher number of fins for larger surface area for convection. Furthermore, the overall thermal conductivity is low.