The Study Of The Interaction Of Graphene And Metallic Nanostructure

Graphene has been a concern since the discovery of the beginning, because of its novelty physicochemical properties. The study of graphene is from its own mechanics, calorifics, optics and electricity at the beginning, and now gradually extended into the study of its derivatives with other nanomaterials composite. The unique nature of metallic nanostructures is completely different from macroscopic bulk matter, small molecules or other nano-structures. If it is combined with graphene will produce what kind of wonderful nature, will bring whatnew applications. These are the answers I hope to find in this thesis. Thethesis focuses on the interaction between graphene and its derivatives with metallic nanostructures. Based on the preparation of composite materials, advantages and prospects of graphene with metallic nanostructures composite systems aresystematically discussed in many aspects, such as biosensing, surface-enhanced Raman scattering, catalysis and fluorescence. By characterization, calculation and discussion, the thesis argues that rational use of the interaction of graphene and metallic nanostructures can make more sensitive sensor, the Raman signal more obvious, catalysis more effective orfluorescence more controllable. These findings will help people further understand the mechanism of interaction of graphene with metallic nanostructures, and provide application basis in many areas. The main innovations of this thesis are as below:1. In the preparation of graphene and metal nanostructures, using electroless deposition techniques and in situ reduction step, the gold particles are compounded into the CVD growth graphene and chemical redox graphene, respectively. Electron microscopy, energy dispersive spectroscopy and X-ray photoelectron spectroscopy results show that the metal particles can be uniformly dispersed in the graphene sheet or edges.(J. NanoscI. Nanotechno.2014,14,3412; Paten, CN102513533A)2. In biosensing, in order to be more sensitive and convenient detection of β2agonist, the graphene and gold nanoparticles compositesare used to trace detectβ2agonist. Using this method, β2agonists detection limit is down to10-10M, and the concentration of the analyte can be detected in the linear range:10-6～10-10M. To strictly control the β2agonist class of drugs abuse, this work provides a new testing idea.(Chinanano2013,135; Talanta2013,115,992; Chem. Phys. Lett.2013,574,83;)3. In the surface-enhanced Raman scattering (SERS), the proposed graphene and gold nanoparticles composites are used as a method of SERS substrate.The Raman signal of Rhodamine6G test results show that the enhancing effect of composite substrate is much better than pure gold nanoparticles substrate. More importantly,by further test and discussion in detail, the composite substrate is a very suitable means for SERS enhancement of chemical mechanisms. These findings would provide a new insight on better understanding of chemical-enhanced Raman mechanism and open up a new way of the graphene-metallic nanoparticle substrate applications.(Chem. Phys. Lett.2013,582,119)4. In catalysis, the chemiluminescence (CL) performance of luminol is improved using graphene and gold nanoparticle composites as catalyst. The size effect of particle and the assisted enhancement effect of graphene are studied and discussed in detail. Based on the discussion, an optimal, sensitive and stable CL system is proposed. Finally, we utilize the system as a sensor to detect hydrogen peroxide and organic compounds containing amino, hydroxyl, or thiol groups. The CL system might provide a more attractive platform for various analytical devices with CL detection in the field of biosensors, bioassays and immunosensors.(Chinese Phys. B2014,23,048103)5. In terms of fluorescence modulation, an effective strategy to enhance and modulate the photoluminescence (PL) of graphene quantum dots (GQDs) in the vicinity of a single silver nano-octahedron (SNO) is proposed utilizing three-dimensional finite-difference time-domain calculations. The SNO is designed to act as a multifrequency plasmonic antenna with multiple plasmon resonance modes covering multiple emission peaks of GQDs. The spectral modifications of spontaneous emission are investigated with the variations of the GQD’s position and dipole moment orientation relative to the SNO. The PL colour of the GQD can be precisely adjusted between blue and green through the strong interaction with the designed antenna. The multicolour features of GQDs will also facilitate their potential applications as eco-friendly and multifunctional optical probes. The study contributes to a deeper understanding of the PL properties of GQDs near the metallic nanoparticles.(.Phys. Chem. Chem. Phys.2014,16,4504)...