电化学法制备石墨烯薄膜及其导热性能研究

采用优化的先浓硫酸氧化插层、再稀硫酸二次氧化插层的两步电化学氧化方法,将石墨纸电极剥离成缺陷较少、水平尺寸较大的氧化石墨烯薄片; 利用平板刮涂的方式将氧化石墨烯的N-甲基吡咯烷酮分散浆料组装成氧化石墨烯薄膜,经由3000 ℃的高温石墨化热处理过程和后续辊压操作,获得了性能优异的石墨烯导热薄膜材料,导热系数达到了3090 W/(m·K)。讨论了氧化石墨烯前驱体的氧含量、中值粒径数据及薄膜厚度对石墨烯薄膜导热性能的影响,并分析了其作用机理,可为石墨烯在导热领域的商业化应用提供参考。

Thermal Conductivity of Graphene Films Prepared by Electrochemical Synthesis

Graphene paper electrode was exfoliated into graphene oxide nanosheets with few defects and larger lateral size by adopting an optimized two-step electrochemical oxidation method, including oxidation intercalation firstly with concentrated sulfuric acid, and then with diluted sulfuric acid. The N-methylpyrrolidone dispersed slurry of graphene oxide was assembled into graphene oxide films by blade coating. It was then subjected to graphitization heat treatment at a high temperature of 3000 ℃ followed by roller press, leading to the graphene film with a thermal conductivity up to 3090 W/(m·K). After that, the effects of oxygen contents, median particle size of graphene oxide precursors and film thickness on the thermal conductivity of graphene film were discussed, and the relative mechanism was also revealed. This study can provide  references for commercial application of graphene in the field of thermal conduction.