Preparation, Spectroscopic Properties Of Micro-, Nano-aggregates Containing Graphene, Silica And Metal Complexes

Graphene has made people aware of that their development could bring new opportunities for the research in the subjects of physics, chemistry and materials science and technology because of their special structure, unique physical and chemical properties. Along with the deepening of research, the construction of graphene-based nano-aggregates has become one of the most important research frontiers in nanotechnology. The purpose of this dissertation is to prepare the graphene-based micro-, nano-aggregates by chemical method combined with self-assembly process and to study their surface enhanced Raman scattering(SERS). These micro-, nano-aggregates have potencial applications in the regions of optoelectronic devices, super capacitors and sensors.The contents of this dissertation may be divided into three parts as follows:(1) GO was prepared by using Hummers’ method combining ultrasonic peeling process. GO/Cu(Met)2, GO/Si O2 and r GO/Ag NPs/Cd C micro-, nano-aggregates were constructed by microemulsion process, St?ber method and self-assembly process, respectively. The as-prepared micro-, nano-aggregates were characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR), respectively.(2) The Cu(Met)2 single crystal was growed by gel diffusion method, and Co(bpy)2(N(CN)2)2 single crystal by solute crystallization method. The crystal structures of as-prepared metal complexes were studied by single crystal XRD, FTIR and Raman spectroscopy, respectively. The nuclear site group analysis method was employed to determine the number of infrared and Raman active modes for the metal complexes.(3) r GO/Ag NPs and Si O2/Ag NPs micro-, nano-aggregates were prepared by liquid phase reduction method. r GO/Ag NPs/Cu(Met)2 nano-aggregates were prepared by liquid co-precipitation method combined with adjusting the p H value of mixed liquids and Si O2/Ag NPs/Co(bpy)2(N(CN)2)2 aggregates by self-assembly process. The as-prepared micro-, nano-aggregates were characterized by SEM, TEM, FTIR and Raman spectroscopy, respectively. Analysis of surface enhanced Raman scattering of the micro-, nano-aggregates revealed that Cu(Met)2 molecular plane exhibited a perpendicular orientation and Co(bpy)2(N(CN)2)2 molecular plane exhibited a sloping orientation with respect to the surface of silver nanoparticles.