Kim Yuna, Park Soo-Jin, Kim Kwang Man, Lee Young-Gi, Kim Seok
J Nanosci Nanotechnol. 2014 Dec;14(12):9289-93. doi: 10.1166/jnn.2014.10118.
Graphene nanosheets (GNS)/nickel oxide (NiO) composites were synthesized by a chemical method with a various amount of nickel precursor. For all composites, NiO nanoparticles were well decorated on the surface of graphene nanoplatelets. The structure and morphology analysis was performed by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). We confirmed that pure NiO particles are aggregated with each other and NiO particles dispersed on GNS prevent graphene from restacking in the composite. Electrochemical properties were also examined by cyclic voltammetry (CV). The optimum ratio of GNS to NiO was 1:20 (2 g of NiCl2 x 6H2O), showing the highest specific capacitance of 1034.7 Fg(-1) at 2 mV s(-1). This value was much higher than that of pure NiO and GNS, respectively. However, as the amount of nickel precursor increased, the specific capacitance displayed a decreasing tendency. It was probably due to the large agglomeration of NiO particles in high content of NiCI2 x 6H2O.
通过化学方法，使用不同量的镍前驱体合成了石墨烯纳米片（GNS）/氧化镍（NiO）复合材料。对于所有复合材料，NiO纳米颗粒都很好地装饰在石墨烯纳米片的表面上。通过场发射扫描电子显微镜（FE-SEM）、透射电子显微镜（TEM）和X射线衍射（XRD）进行结构和形态分析。我们证实，纯NiO颗粒相互聚集，而分散在GNS上的NiO颗粒可防止复合材料中的石墨烯重新堆叠。还通过循环伏安法（CV）研究了电化学性能。GNS与NiO的最佳比例为1:20（2 g NiCl₂·6H₂O），在2 mV s⁻¹时显示出最高比电容1034.7 Fg⁻¹。该值分别远高于纯NiO和GNS的比电容。然而，随着镍前驱体用量的增加，比电容呈现下降趋势。这可能是由于在高含量的NiCl₂·6H₂O中NiO颗粒大量团聚所致。
