Preparation And Characterization Of Luminescent Materials ZnO:Eu³⁺

ZnO, aâ…¡-â…¥ semiconductor with a wide band gap(Eg=3.37eV) and a large excitonic binding energy (60meV) at room temperature is a potential candidate for applications in short-wavelength optoelectronic devices, including light emitting diode, solar cells, semiconductor laser and UV detectors. In this experiment, the luminescence materials was respectively synthesized by chemical precipitation method and high temperature-energy ball milling method, which used ZnO as the matrix and Eu3+as the sensitive components. This luminescence materials could be applied to various abominable nature conditions, such as cold north, fervent south and tableland with strong ultraviolet radiation, in addition, it could be widely used as the palette of aircraft coating. The powders was characterized by XRD, SEM, LPA and FL. Finally, the optimum preparation techniques of the two methods were obtained.The results of the study are listed as follows:(1) In this paper, ZnO:Eu3+powders were prepared, using C4H6O4Zn-2H2O, EU2O3,(NH4)2CO3as raw materials, by chemical precipitation method and high temperature-energy ball milling method. The XRD result showed that the hexagonal wurtzite phase ZnO:Eu3+powders were both obtained through the two methods; the emission spectrum showed that the ZnO:Eu3+powders were effectively excited by the excitation of465nm and series of characteristic Eu3+emissions were observed, one peak of618nm was attributed to the5D0â†'7F2transition of Eu3+, which eradiated characteristic red luminescence.(2) The effect of the pH value, the precipitation temperature, the aging time, the calcination temperature and the doping content of Eu3+on the ZnO:Eu3+powders were studied by the chemical precipitation method. Results showed that the optimum pH value was7.5, precipitation temperature was50℃, calcination temperature was900℃and doping content of Eu3+was1.0%mol.(3) The precursors synthesized by chemical precipitation method as raw materials, the influence of the ball to material weight ratio, the ball milling temperature, the ball milling time and the doping content of Eu3+on the ZnO:Eu3+powders were discussed by the high temperature-energy ball milling method. Results showed that the optimum ball to material weight ratio was20:1, ball milling temperature was450℃, ball milling time was3h and doping content of Eu3+was2.5%mol.(4) The two methods were compared. It was demonstranted that the high temperature-energy ball milling method could reduce the synthesize temperature of ZnO:Eu3+powders about450℃; the ZnO:Eu3+powders prepared by high temperature-energy ball milling method was smaller and well-distributed. During the process of high temperature-energy ball milling, the difficutly of doping in ZnO was reformed and the doping content of Eu3+was promoted about1.0%mol.