Preparation And Luminescence Characteristics Research Of Binary Metal Borates Nanofibers

Lots of literature shows that borate fluorescent materials have excellent color rendering index,lumen efficiency and temperature sensing performance,and have been used in LED luminescence and non-contact optical detectors and other fields.One-dimensional nano material having a high specific surface area,and good flexibility characteristics,has been successfully coated on a blue LED chip,to achieve a uniform white light emission,overcomes many problems in the conventional process.And one-dimensional light emitting material in the temperature sensing performance also exhibited excellent performance.Hence,the analysis of binary metal borate materials with one-dimensional structure has high value.Binding using electrospinning high temperature sintering process,the preparation of Eu³⁺ion doping Sr₃Y₂（BO₃）₄ nanofibers.XRD results show that when Sr₃Y₂（BO₃）₄ system nanofibers are prepared according to the ideal chemical ratio,after high temperature sintering at 1000℃,the product will not only produce Sr₃Y₂（BO₃）₄,but also a certain amount of Y₂O₃.When the excess of boric acid is 30%,After sintering at 1000℃,the product was single phase structure of Sr₃Y₂（BO₃）₄,which was not changed by doping of Eu³⁺ions.SEM consequence found that after the nanofibers were sintered at 1000°C,the product still remains fibrous,and the diameter was reduced to 300 nm.Excitation spectra showed the product to have strong absorption of 395nm UV light and blue light at 468 nm,according to the emission spectrum,the products excited by 395 nm and 468 nm have the characteristic luminescence of Eu³⁺ions.The color coordinate results show that when the excitation wavelength was adjusted from ultraviolet light（395 nm）to blue light（468 nm）,the luminescence of Sr₃Y₂（BO₃）₄:Eu³⁺material changes from orange-yellow to orange-red region.The results of temperature sensing characteristic find that the temperature range of 323-563 K,the maximum temperature measurement relative sensitivity Sr appears at 323 K,and its value is0.025%K^-1,and the absolute sensitivity Sa was the maximum at 563 K,and its value is0.000039 K^-1.The Dy³⁺doped Sr₃Y₂（BO₃）₄ nanofibers were obtained by the same method.XR D results showed that the crystal structure of the matrix did not change.SEM results show that the fiber precursor still maintains the fiber morphology after being sinter ed at 1000℃,and the fiber diameter was reduced to about 200 nm.Under excitation at an excitation wavelength of 352 nm,there were two obvious luminescence peak s at 484 nm and 575 nm,respectively,which belong to the characteristic emission of Dy³⁺ions.The temperature sensing characteristics show that Sr and Sa were the lar gest at 303K.Sr=0.02153%K^-1,Sa=0.01289 K^-1.Electrospinning technology with a high temperature sintering process,the preparation of Eu³⁺ion doping Na Sr BO₃ nanofibers.XRD consequence found that the sintered at 800℃,the materials having a matrix structure of orthorhombic Na Sr BO₃.SEM results found that the morphology of the product after sintering at 800°C was composed of rough large crystal grains,and the diameter increases to about 800 nm.the luminescence spectrum shows that the Na Sr BO₃:5%Eu³⁺sample exhibits the characteristic luminescence of Eu³⁺ion.Compared with the Sr₃Y₂（BO₃）₄:5%Eu³⁺sample,at the same doping concentration,the Na Sr BO₃ matrix has better crystallinity,so Na Sr BO₃:5%Eu³⁺has higher luminous efficiency.The temperature sensing characteristics show that in the temperature range of 323-563 K,the maximum temperature measurement relative sensitivity Sr and absolute sensitivity Sa both appear at323 K,Sr=0.022%K^-1,and Sa is 0.006 K^-1.