氢碘酸预还原制备导热石墨烯膜

Preparation of Heat-conducting Graphite Film by Hydroiodic Acid Prereduction

由氧化石墨烯制备得到的石墨烯膜在还原过程中一般采用热还原手段。然而热还原过程中产生含碳气体,不仅导致碳原子的损失并在碳网络上留下了缺陷,同时膜内气体的产生使得石墨烯片层排列有序度下降,以上两者都对石墨烯膜的导热性能产生不利的影响。因此,本文对热还原加以改进,即在热还原之前使用氢碘酸对GO膜进行还原,使得氧化石墨烯膜的含氧官能团含量降低。而在后续热还原过程中,由于产生的含碳气体减少,膜内片层排列有序度提高,同时还使得ID/IG从2.06降至1.41,晶体缺陷减少。最终使得石墨烯膜残碳率从37.1%提升至49.3%。石墨烯膜热导率从1067.4W/(m·K)提升至1287W/(m·K),石墨烯膜的导热能力显著增加。

The graphene film prepared from graphite oxide is generally reduced by thermal reduction.However,the production of carbon containing gas during the thermal reduction process not only leads to the loss of carbon atoms and leaves defects on the carbon network,but also reduces the order of graphene layer arrangement due to the generation of gas within the membrane.Both of the above have adverse effects on the thermal conductivity of graphene films.Therefore,the thermal reduction is adjusted in this paper,that is,before the thermal reduction,the GO film is reduced with hydroiodic acid,so that the oxygen functional group content of graphite oxide film is reduced.In the subsequent thermal reduction process,due to the reduction of carbon containing gas generated,the order of the layer arrangement within the membrane is improved,and the ID/IG is also reduced from 2.06 to 1.41,indicating a reduction in crystal defects.Ultimately,the carbon residue rate of the graphene film increased from 37.1%to 49.3%.The thermal conductivity of the graphene film increased from 1067.4W/(m·K)to 1287W/(m·K),indicating a significant increase in the thermal conductivity of the graphene film.