| Recently, intense research activity has been focused on nano-sized luminescence materials regarding its unique optical characteristics comparing with the bulk phosphor. These natures are mainly caused by the small size effect, surface effect, quantum size effect and quantum tunnel effect. In addition, nanophosphor also exhibits some advantages on the aspect of the application that they are specially employed to acquire miniature luminescence device and high resolution display equipment. Therefore, this paper is mainly focus on the synthesis and investigation of photoluminescence of nanophosphors as well as comparing with the bulk phosphor.At present, the commercial blue phosphor for VUV application is BaMgAl10O17:Eu2+, which has the advantages of high quantum efficiency and good color purity. However, there are two serious problems of BaMgAl10O17:Eu2+ during the manufacture:one is the high reaction temperature leading to high energy consumption, high production cost and easily sintered; the other is the degradation of BaMgAl10O17:Eu2+ under the thermal and VUV irradiation treatment. Aiming at the above problems, we successfully synthesized BaMgAl10O17:Eu2+ nanophosphor by sol-gel method, which reduced the synthesis temperature about 350℃. Through the introduction of surfactant cetyl-tri-methyl-ammonium bromide (CTAB) in the sol-gel process,BaMgAl10O17: Eu2+ nanophosphor with good emission intensity and thermal stability was achieved. With the purpose of impelling BaMgAl10O17:Eu2+ nanophosphor for application, chemical doping was employed on the basis of the optimum condition. It was found that the codopant of Ca2+ and Mg2+ could further improve its photoluminescence, especially the thermal stability. The optimum nanophosphor presented a considerable emission intensity and higher thermal stability than the commercial one.Tungstates are expected to be the new hosts of VUV luminescence materials because of their broad absorption in VUV region. In this paper,30nm,50nm and 70nm of CaWO4 nanophosphors were synthesized by hydrothermal reaction. From the investigation of their luminescence properties, blue shift was observed in the absorption and excitation spectra. Besides, it was found in CaWO4 nanophosphors that the concentration of oxygen vacancy was increasing with the reduction of the particle size. A possible mechanism for the relationship was given based on the formation energy of oxygen vacancy in CaWO4 nanophosphor. In addition, we doped Tb3+ and Yb3+ in CaWO4 nanophosphor. The CaWO4:Tb nanophosphor presented the unique higher quenching concentration comparing with the bulk. By maintaining the concentration of Tb3+, the nano- CaWO4:Tb also exhibited longer life decay time than that of the bulk. For CaWO4:Tb, Yb luminescence material, the energy transfer from Tb to Yb was observed through the investigation of its UV-VIS-NIR luminescence properties. Due to the overlap between donor characteristic emission and acceptor characteristic absorption was absent and the sum of the absorption energy of the two acceptors equaled the emission energy of the one donor, NIR quantum cutting was proved in CaWO4:Tb, Yb. By calculating, the quantum efficiency of CaWO4:0.01Tb,0.2Yb reached 140.4%. According to the energy of Yb3+2F5/2-2F7/2 emission is just above the band gap of the crystalline Si, the material could be potentially applied in silicon-based solar cells.
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