| With the research,application and development,phosphor materials are gradually used in various fields of human life,including medicine,information storage,anti-counterfeiting,lighting,botany,and so on.In other words,phosphor material is in many industries with its unique advantages played an irreplaceable role.The development of new applications of phosphor materials and combine phosphor materials with other disciplines has become a new research topic for phosphor materials.However,in the time and time again of innovation and collision,we hope to solve some fundamental problems of other disciplines,but also hope to develop new applications of phosphor.materials.The aluminate phosphor material,as the leader of phosphor field,the excellent optical properties of the sample are still unsurpassed after many years.In this paper,the excellent SrAl12O19 fluorescent material with a variety of spatial polyhedral configuration is analyzed,and the preparation,characteristics and application research of SrAl12O19 luminescent materials doped with Cr3+,Ti3+,Ce3+and Mn2+respectively are mainly studied.Specific research contents are as follows:1.It is found that the deep trap is the main reason for the afterglow emission in SrAl12O19:Cr3+ and the Cr3+ doped in different Al-O lattice ligands of SrAl12O19 would show peculiar dual band luminescence properties.The multi-band and broadband persistent luminescence 650-1100 nm peaking at 688 nm and 793 nm from Cr3+-doped SrAl12O19 are systematically studied via the structural and spectroscopic analysis.Solid state nuclear magnetic resonance allows the visualization of various coordination configuration in SrAl12O19,thus offering the theoretical possibility of Cr3+ can be doped with different Al-O lattice ligands to control the different luminescence wavelengths of Cr3+.Deep tissue ex vivo imaging and in vivo imaging in mice both demonstrate that multi-band-emissive SrAl12O19:Cr3+ has a superiority of high-quality NIR bio-imaging in biologically transparency window than single band-emissive(only having the emission at 688 nm)SrAl2O4:Cr3+ as a contrast,although SrAl2O4:Cr3+ has a higher luminescent intensity and longer persistent duration at 688 nm.Besides,the driving force of carriers release is only discovered from the deep trap by measuring the thermoluminescence spectra,which is different from the generally-accepted shallow-dependent afterglow-emitting process.These findings pave the way for opening a vista of potential avenues for the enhancement of signal-to-noise ratio,the improvement of imaging quality,same as the understanding of trapping and de-trapping process in long persistent phosphors.2.The development of a smart sunlight window to promote plant growth without the need for fertilizer is of considerable interest in both materials' science and biology.In particular,green light(500-620 nm)is considered an inefficient wavelength in the solar spectrum for photosynthesis.In contrast,blue(400-500 nm)and far-red and near-infrared photons(650-850 nm)are preferable for plant growth.Here,we report on a smart window that contains SrAl12O19:Ti3+ nanoparticles that can transparent in blue region of the solar spectrum but can selectively convert the less favorable green light to the most useful far-red and near-infrared light with respect to photosynthesis.When cultivating beneath such a smart window,plants,such as a garlic bolt and oxalis demonstrate remarkably improved longitudinal and lateral growth under direct outdoor sunlight or green and white LED room light.This method offers a simple way to maximize the use of solar energy for more effective plant cultivation without the need for fertilizer.In addition,such operable light converting nanoparticles may also lead to a wide variety of applications in the fields of biophotonics and photonics.3.Visible and near-infrared long afterglow materials in different wavelengths have been widely reported,but few of them have been studied.In this dissertation,photoluminescence(PL)persistent luminescence(PersL)and optical stimulated luminescence(OSL)with 300 nm emission wavelength have been realized on SrAl12O19:Ce3+,Sc3+ phosphor,which fills the gap of PersL in UVB range.Thermoluminescence(TL)spectra show that the shallow trap which is induced by the Sc3+ co-doping plays an important role in contribution to PersL,while the deep trap dominates the generation of OSL.Owing to the appearance of the deep traps,the OSL under different ranges light excitation(700-900 nm)are also observed.Due to the features of PersL and OSL in UVB range,SrAl12O19:0.5%Ce3+,5%Sc3+ have tremendous applications in the treatment of specific diseases,anti-fake and optical information storage,and so on.4.In the current big data era,state-of-the-art optical data storage has become a front-runner in competing data storage technologies.In this work,we propose an information storage prototype using optical stimulated luminescent phosphor of SrAl12O19:Mn2+,Gd3+,which converts the photon into trapped electrons and partially releases them in a form of luminescence when irradiated by infrared irradiation,rendering an optical information storage ability.Information storage can be realized in both graphical and digital formats.In this way,graphical patterns can be stored and rejuvenated by infrared irradiation,and a set of digital data is recorded step by step by a home-make decoding system,completing an optical data reading process.This dissertation provides a practical example for future application of writing-storing-readout-erasing-rewriting integrated optical information storage. |
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