Reaserch In Fluorescence And Temperature Characteristics Of Rare Earth Ions Doped Nano Materials

Along with the development of the science and technology, the up-covnversion luminescence materials which were doped rare earth have been widely concerned owing to its excellent properties. Therefore the materials have become the focus of the research at home and abroad. The materials have very important application value in the field of petrochemical engineering,fluorescence detection,3D Volumetric Displa and military defense. The temperature plays more and more important role in our life, dustrial production and national defense. The temperature measurement is also important to our body, especially for the early diagnosis and treat. Meanwhile the up-covnversion luminescence materials have application in biological detection and temperature measurement. So we choose NaYF4 nanoparticles as matrix material, it had lower phonon energy. We choose solvothermal synthesis to the NaYF4:Yb3+,Tm3+nanoparticles,the core NaYF4:Yb3+, Tm3+/NaYbF4 nanoparticles and the core NaYF4:Yb3+,Tm3+/NaYF4 nanoparticles. Through the analysis of the XRD and TEM, the nanoparticles was small, uniform and monodispersive.With the excitation of the 980 nm diode laser, we study the upconversion fluorescence spectroscopy of the NaYF4:Yb3+,Tm3+ nanoparticles with the change of Tm3+ ion doped concentration. The fluorescence intensity of the NaYF4:Yb3+,Tm3+nanoparticles presented first increases and then decreases in near infrared(695nm and 801nm). The fluorescence intensity is the strongest when the Tm3+ ion doped concentration is 1%mmol. Through the upconversion fluorescence spectroscopy and fluorescence lifetime, we analyze the effect of the two fluoride shell on the fluorescence enhancement mechanism. We got the NaYF4 shell is more suitable for biological fluorescence temperature measurement. Based on the variation of emission intensities with the pumping powers, the upconversion mechanisms of the NaYF4 : Yb3+, Tm3+/NaYF4 nanoparticles has been discussed. The cooperative upconversion of the Yb3+ ion played an important role in the excited state distribution of Tm3+ions.With the excitation of the 980 nm diode laser, we choose the doped concentration of theTm3+ / Yb3+ion is 1%mmol/20%mmol as the research object. Through the thermally coupled levels( 3F2,3, 3H4)of the Tm3+ ion, we analyse the biological fluorescence temperature characteristics of the bare core nanocrystalline and nuclear shell materials nanocrystalline at the range of 310K-430 K. And the good sensitivity of the NaYF4:Yb3+,Tm3+/NaYF4 nanoparticles proved its application prospect in biological fluorescence. Meanwhile temperature measurement which based on fluorescence intensity by using the NaYF4:Yb3+,Tm3+ nanoparticles is firstly proposed by us. With the excitation of the 980 nm diode laser,we study the fluorescence temperature characteristics of the energy level 3H4. We find the fluorescence intensity is linear with temperature.