Modulation Of Localized Surface Plasmon Resonance Of Noble Metal Nanostructures And Its Optoelectronic/Photoacoustic Applications

Noble metal nanostructures(NSs)and their localized surface plasmon resonance(LSPR)have been widely used in micro-nano optics,optoelectronics,biomedicine,etc.In recent years,through unremitting research,researchers have gained deeper and deeper understanding of the properties and applications of noble metal nanostructures and LSPR.However,further research is needed on the relationship between the properties and structure-activity of complex NSs and LSPR,and the improvement of the application level of LSPR.In this dissertation,the relationship between the morphology,dielectric environment and the evolution of optical properties of Au,Ag and their alloy NSs were studied,and then the applications of Au,Ag NSs and their LSPR photoelectric and photoacoustic effects in photoelectric detection and photoacoustic microfluidic pump were explored.1.Evolution of morphology and optical properties of metal oxide(MO)/Au nanoparticle(NP)hybrid films.The corresponding MO/Au nanoparticle hybrid films solid-state-dewetting(SSD)growth of Au NPs and subsequent sol-gel deposition of MO.Compared with the isolated Au NP arrays,the Mo/Au NP hybrid films have significant LSPR absorption enhancement and red shift.By systematically controlling the film thickness,the evolution of optical properties of the hybrid film can be divided into three stages:(?)Rapid enhancement,(?)Slow enhancement and(?)Decay.With the aid of finite-difference time-domain(FDTD)calculation,the absorption properties and near-field distribution of MO/Au NPs hybrid films were studied.2.The optical properties of Au network NSs and the enhancement effect of optoelectronic devices excited by polychromatic light.The Au network NSs made by low-level SSD were investigated in this work.It is observed that the Au network NSs have a wider LSPR absorption in the visible and mid infrared region.With the help of FDTD simulation,the electric field distribution of Au network NSs and extinction efficiency of different wavelengths are studied systematically.The results show that the irregular Au NSs have strong LSPR absorption in the near infrared region.In this work,the application of Au network structure in TiOx photodetector is studied.Under the excitation of polychromatic light,the photocurrent performance of TiOx/Au network NSs is compared and evaluated,and it is concluded that Au network NSs have great potential in the scene of polychromatic LSPR excitation.3.The photoacoustic microfluidic pump(PMP)with easy manipulation using AgAu alloy NPs with adjustable LSPR was investigated.Alloy NPs with adjustable LSPR peak are successfully prepared through SSD and investigated by FDTD simulation.Based on the alloy NPs,PMPs excited with 450 and 532nm lasers are successfully fabricated and the jetting velocity show a close correlation to the laser power with both lasers.The experimental results show that the jetting produced by the sample with low Au content excited by 450nm laser is more stable than that produced by the sample with high Au content irradiated by 532nm laser.This work exhibits the important significance of LSPR material selection for high-stability PMP designing.