The Study On The Property Of Upconversion Emission Of Er³⁺,Yb³⁺ Doped Nanosized YVO₄

Er3+,Yb3+ doped nanocrystal YVO4 powders with different sizes were prepared by the precipitation method, In this study, we investigated the upconversion emission spectrum of Er3+,Yb3+ co-doped YVO4 nanocrystals and found that when the nanoparticle decreases, the red emission increases, the green emission decreases,that is to say as size of The nanoparticle decreases, the red-green up-conversion of the samples increases.The luminescence dynamics process of the energy levels and the infrared absorption spectrum of YVO4 nanocrystals were investigated, found that the particles of smaller size are closer to the surface where the OH- groups possessing highest phonon energy are located,and this will gain the rate of non-radiative from 4I11/2 level to 4I13/2 level. Then influenced the upconversion emission ratio of red to green. Also texted the temperature emission spectrum of different particle sizes YVO4: Er3+ and Yb3+ samples. Investigated in temperature sensing properties and sensitivity and comparied with three luminescent materials,we got to know in a relatively wide range of sensing temperature(293–603K),the sensitivity of nanosized material was better than bulk material,,so the nanosized materials was better applied in temperature sensing than bulk materials. The main innovations of this work are the following:1.we use a precipitation method, compared with other preparation methods, this method is simple, convenient to make, easy to mass production and cost little,all these make this method more and more widely used In the preparation of rare earth doped nanometer materials。2.According to the emission spectrum of YVO4 nanocrystal, normalized and concluded that as the size of sample changed the integrated intensity ratio of red to green changed too。The smaller size of the sample is,the larger amount of emission spectrum will be,that is to say the integrated intensity ratio of red to green will be larger too。3.By comparing the Temperature sensing properties of these three materials, trying to find the material which have the better property。...