氢氧化镍/还原氧化石墨烯复合材料的制备及其电化学性能

Preparation and Electrochemical Properties of Nickel Hydroxide/Reduced Graphene Oxide Composites

以六水合硝酸镍和氧化石墨烯为原料,多孔泡沫镍为基底,尿素为沉淀剂,十六烷基三甲基溴化铵(CTAB)为分散剂,采用简单的一步水热还原法,制备Ni(OH)_(2)/RGO复合电极材料。对制备得到的Ni(OH)_(2)/RGO电极材料进行形貌结构表征,并通过循环伏安(CV)和恒电流充放电(GCD)测试研究了材料的电化学性能。通过X射线衍射(XRD)分析确定了Ni(OH)_(2)和Ni(OH)_(2)/RGO的晶型,SEM结果表明,丝绸状还原氧化石墨烯片有效且均匀地分布在Ni(OH)_(2)层的表面,在水热过程中Ni(OH)_(2)片原位生长在泡沫镍上,形成三维多孔多层多样化结构。与纯Ni(OH)_(2)相比,1 A/g下纯Ni(OH)_(2)的比电容为1930 F/g,而Ni(OH)_(2)/RGO比电容高达2508 F/g。这些结果表明Ni(OH)_(2)/RGO是一种很有前途的超级电容器电极候选材料。

Ni(OH)_(2)/RGO composite electrode materials were prepared from nickel nitrate and graphene oxide by one-step hydrothermal reduction using porous nickel foam as substrate,urea as precipitant and hexadecyl trimethyl ammonium bromide(CTAB)as dispersant.The morphology and structure of Ni(OH)_(2)/RGO electrode materials were characterized,and the electrochemical properties of the materials were investigated by cyclic voltammetry(CV)and galvanostatic charge-discharge(GCD)tests.The crystal forms of Ni(OH)_(2) and Ni(OH)_(2)/RGO were determined by X-ray diffraction(XRD)analysis.SEM images show that the silky RGO sheets are effectively and uniformly distributed on the surface of Ni(OH)_(2) layer.During the hydrothermal process,Ni(OH)_(2) sheets grow in situ on the nickel foam,forming a three-dimensional porous multi-layer diversified structure.Compared with pure Ni(OH)_(2),the specific capacitance of pure Ni(OH)_(2) at 1 A/g is 1930 F/g and the specific capacitance of Ni(OH)_(2)/RGO is 2508 F/g.These results indicate that Ni(OH)_(2)/RGO is a promising electrode candidate material for supercapacitor.