以氧化石墨为前驱体,氢卤酸为诱导还原剂,采用化学还原法在温和条件下制备石墨烯气凝胶组装体。利用扫描电镜、X射线衍射、拉曼光谱、X射线光电子能谱及热重等分析手段对石墨烯气凝胶组装体的结构及性质进行表征,以研究氢卤酸的种类及浓度对石墨烯气凝胶的形成、结构及性质的影响。结果表明:相比于HBr和HCl,利用H+与I-的协同作用,HI能够有效的诱导石墨烯气凝胶组装体形成。相对于氧化石墨,所制备的石墨烯气凝胶的热稳定性和导电能力均得到了显著的提高。将石墨烯气凝胶作为超级电容器电极材料,表现出优异的电化学性能。
Three-dimensional( 3D) graphene aerogels were fabricated from graphene oxide using HBr,HCl and HI as promoters.The structures and properties of the aerogels were characterized by scanning electron microscopy,X-ray diffraction,Raman spectroscopy,X-ray photoelectron spectroscopy and thermal gravimetric analysis. It was found that 3D graphene aerogels can be made in the presence of HI. Their formation is promoted by the synergistic effects of the acidic H+and the reductive I~-. The electrical conductivity and thermal stability of the aerogels were significantly improved compared with those of graphene oxide. When the aerogels were used as supercapacitor electrodes,excellent specific capacitance and rate capability were achieved.