Study On Preparation Of Nano Particles By Photochemical Deposition And Plasmon-driven Surface Catalysis

We refer to the Raman scattering spectrum as the fingerprint of matter,which can be used to determine the type of molecule or even the structure of a molecule.Because the intensity of the Raman scattering light is about ten thousand of the total scattered light intensity,it's hard to get only the molecular Raman signal.The enhancement of the electromagnetic response of the local surface plasmon enhanced Raman scattering and the effect is limited by the nanostructure.The surface plasma vibration on the rough surface is more intense,and can be coupled with a strong electromagnetic field.Thus,a great deal of research has been done on the Raman scattering enhancement of the substrate,and a great progress has been made.Traditional methods,such as magnetron sputtering,chemical etching and photolithography,have been developed.However,some of these methods require too high,some of the operation is too complex,and some even the cost is too high,seriously restricting the development of SERS substrate preparation.To make good preparation of SERS substrate using a new method in this paper,the method has simple operation,but also can accurately control the substrate surface roughness,this is a good choice for the study of Raman spectroscopy,In our work,we can change the external conditions to prepare the substrate with different roughness,and obtain the Raman signal of the adsorbed substrate molecule,The plasmon driven surface catalysis(PDSC)reaction is also investigated on the lithium niobate(LiNbO3)film with photochemically deposited Au NPs.The surface enhanced Raman scattering(SERS)spectra indicates the performance of PDSC reaction on substrate with various Au3+ concentration in photochemical deposition are obvious different.Combining structure characterization and electromagnetic field simulation,this result is mainly contributed to the surface plasmon coupling between Au NPs.Furthermore,the results also point out the exposure time in photochemical deposition play an important role in the PDSC reactions.Our studies on photochemically deposited Au NPs substrate provide a strong support and further understanding to the research on PDSC reaction,also to other surface plasmon related fields.In addition,the finite difference time domain(FDTD)method is used to simulate the surface plasmon driven catalytic reaction.Another job is to study the photochemical sink nanosheets,by controlling the reaction time and light intensity,the synthesis of nanosheets of different sizes,and to study the metal ferroelectric material changes in the excitation potential of ultraviolet light,help to our understanding of ferroelectric materials and metal materials in contact.