Recently, the research group of Li Qingwen, a researcher of Suzhou Nano Institute of Chinese Academy of Sciences, introduced high-conductivity and high-conductivity copper nanoparticles into carbon nano-tube paper to prepare new carbon nano-tube-based heat dissipation materials with high thermal conductivity and conductivity. The relevant results are published in the journal Carbon.
It is understood that carbon nanotubes have extremely high axial thermal conductivity, so they are highly expected in the heat dissipation materials of high-power electronic devices. However, its small size characteristics, as well as the relatively large contact resistance and contact thermal resistance between carbon nanotubes and the matrix of the composite material, make the thermal conductivity of the existing carbon nanotube composite material far from people's expectation, the practical application is severely restricted.
In the previous research, Li Qingwen's team found that carboxated carbon nanotubes with charged surface can realize high concentration dispersion in silicone grease and form a three-dimensional network with good thermal conductivity, which can greatly reduce the thermal conductivity impedance of silicone grease.
On this basis, by controlling the length, diameter and other factors of carbon nanotubes, the team has prepared flexible carbon nanotube paper with ideal three-dimensional network structure, whose heat transfer impedance is lower than that of thermal conductive silicon grease and commercial heat-dissipating graphite sheet, and it has solid self-supporting characteristics, and can realize efficient heat transfer without polluting the surface of the device when used as the heat conduction interface material.
It is also known that the thermal conductivity and electrical conductivity of pure carbon nanotubes are still lower than people's expectation due to the low density of thermal conductivity network and the large number of carbon nanotubes are overlapped.
For this reason, the team skillfully introduced the high-conductivity and high-conductivity copper nanoparticles into the carbon nanotube paper, and finally successfully realized 10W/(m · K) the thermal conductivity and the conductivity exceeding 105S/m.
Experts said that due to its excellent thermal conductivity, this new material is expected to be applied in the fields of microelectronic interconnection and thermal interface materials.
The work was funded by the National Natural Science Foundation, the "973" plan of the Ministry of Science and Technology, the innovation project of Jiangsu province's industry-university-research cooperation and the international cooperation project of Jiangsu province.
