High thermal conductivity ultra-flexible graphene assembly film developed by Zhejiang University
Release time:
2017-07-10
Source:
Author:
Recently, the superb team of the polymer department of Zhejiang university has developed a high thermal conductivity and ultra-flexible graphene assembly film, with a thermal conductivity of up to 2053W/mK (w/m kelvin), which is close to 40% of the ideal thermal conductivity of single-layer graphene, creating a new record of thermal conductivity of macro materials. At the same time, the material is assembled from micro-wrinkled large graphene sheets and is super flexible. It can be folded 6000 times and can withstand bending 100,000 times.
This latest achievement solves the worldwide problem of high thermal conductivity and high flexibility of macro-materials, and is expected to gain important applications in the fields of efficient thermal management, a new generation of flexible electronic devices and aerospace. The article was published in Advanced Materials.
Electronic appliances generate heat when they are working, and high-efficiency thermal management is needed to ensure their normal operation. The new generation of devices also requires bendability. However, it is often difficult to have both high thermal conductivity and high flexibility of existing macroscopic materials. The emergence of graphene provides a theoretical possibility to solve this contradiction.
It is reported that the superb team creatively put forward the idea of "large micro-folds": large graphene has few defects and can achieve high thermal conductivity; Micro-folds make the material have enough strain space when stretching and bending, which can ensure high flexibility.
Gao Chao told the reporter of China Science Daily that this new idea is very simple to realize. Three steps can be completed: a large piece of graphene oxide aqueous dispersion is formed into a film by scraping; High temperature heat treatment, oxygen-containing functional groups in the film decompose at high temperature to release gas, at the same time, with the increase of temperature, graphene defect structure is gradually repaired, gas is blocked in the graphene film, due to expansion to form a micro airbag.
The researchers also used fragment-free oversized graphene oxide as a raw material to reduce edge phonon escape. At the same time, high temperature heat treatment is used to remove the functional groups on the surface of graphene and repair the internal holes of graphene to obtain a graphene structure with few defects. These structural changes were confirmed by Raman, XRD and transmission electron microscopy. The average thermal conductivity of the obtained graphene film is 1900W/mK, and the highest value reaches 2053W/mK.
Contact Us
Tel:+86-391-3126029（International Trade）
+86-391-3126388（After-Sales Service）
E-mail:hsjcarbon@lomonbillions.com
Fax:+86-391-3126788
Address: Zhongzhan District, Jiaozuo City, Henan Province, China
Message
Copyright © Jiaozuo Zhongzhou Carbon Co., Ltd
Supports IPV6