| Recently, "Green Illumination" becomes an important symbol of the modernization degree for human society, which is also related to sustainable development of nature source. Compared with incandescence and fluorescenc, white light emitting diode (W-LED) has lots of merits, such as energy saving, environment friendly, long lifetime etc. Therefore, as a novel light source, W-LED is one of essential parts of "Green Illumination" attracting much attention. Under the background of W-LED application, we we have a series of research on rare earth ions (REn+)/transition metal ions (TMn+) doped luminescence glass/glass ceramics materials. Compared with the traditional phosphors, luminescence glass/glass ceramics have some distinctive advantages, such as lower manufacturing cost, free of halo effect, adjustable luminescence property etc. In particular, glasses can be molded directly with LED chips, so that free-resin assembly can be realized which will further improve the thermal stability of W-LED set.In the present thesis, the Tb3+, Sm3+, Eu2+, Eu3+, Dy3+, Tm3+ and Er3+ ions dope/co-doped silicate glass, borate glass/glass ceramics and phosphate glass as well as Tb3+, Eu2+ and Mn2+ doped/co-doped phosphate glass are prepared successfully by melting-quenching method. The optical properties are analyzed by absorption spectrum, transmittance spectrum, excitation spectrum, emission spectrum and calculated chromaticity coordinates. The thermodynamic property of glass and the crystalline phase in glass ceramics are studied with the help of by Differential Thermal Analysis and X-ray diffraction measurement. The glass density and the glass network structure information are gained by hydrostatic test method and FT-IR transmittance spectrum. The effect of the increasing Mn2+ concentration on their ligand filed surrounding is investigated by Electron Paramagnanetic Resonance method. Furthermore, We especially discuss the concentration quenching mechanism of REn+ and the energy transfer mechanism between REn+ ions or REn+ and TMn+ ions in glasses. Furthermore, study on irradiation resistance of these luminescence glasses is also included.The relevant research results are listed as follows. Tb3+ and Sm3+ doped in glass can give green and orange-reddish emissions under the UV light excitation, respectively. In co-doped glass sample, the concentration quenching phenomenon of Sm3+ ions and an energy transfer from Tb3+ to Sm3+ ions are also obvious in the emission spectra. Gamma-ray irradiation can cause a new absorption in visible spectrum range for Tb3+/Sm3+ co-doped glass and can reduce the emission intensity significantly. Gamma-ray irradiation can also reduce Tb4+ ions to Tb3+ ions in glass. The glass ceramics could be obtained by the heat treatment of the parent glasses. The SrAl2B2O7 crystal phase containing Tb3+ and Sm3+ ions was precipitated, which plays a positive effect on emission intensity. The blue, green and red emissions from Tb3+, Eu2+ and Eu3+ ions can be observed simultaneously in aluminosilicate glass melted in atmosphere, which results in the final white light emitting. Even under the same melting condition, Eu2+ ion in not stable in zinc silicate glass. However, the energy transfer from Tb3+ to Eu3+ is clearer and the relevant mechanism is quadrupole-quadrupole interaction.The phosphate glass doped with Dy3+ ions emits blue and yellow lights excited by UV light and the emission intensity changes with different glass compositions. When Tm3+ ion is introduced into Dy3+ doped glass, the blue emission is enhanced, which adjusts the combined light into White Light Region. After blue light excitation, Er3+ ions could give several emissions in visible spectrum but the concentration quenching effect is easy to come out even at lower dopant concentration. The luminescence behavior of Er3+ ion in glass is much different from that in glass ceramics. Tm3+ ions could transfer energy to Er3+ ions to strengthen Er3+ red emission in co-doped glass. The phosphate glass doped with Tb3+ and Mn2+ ions can generate green emission and broad red emission band. There is a red shift of Mn2+ emission wavelength with increasing dopant concentration. An energy transfer from Tb3+ to Mn2+ ions takes place under the way of dipole-quatrupole interaction. Eu2+ and Mn2+ ions in phosphate glass can result in a continual emission from violet to red light regions under the 350 nm excitation. Meanwhile, Eu2+ ions can transfer energy to Mn2+ ions with high efficiency and the transfer mechanism is dipole-dipole interaction. The calculated chromaticity coordinates of Eu2+/Mn2+ co-doped glass can move into the white light region, which matches the demand of W-LED application.From the sample preparation and property characterization processes, we can find that the REn+ and TMn+ions express excellent luminescence properties in glass and glass ceramics. The chromaticity coordinates of some samples have moved into white light region, which matches the demand of W-LED application. Therefore, it can be concluded that as a kind of potential luminescence material, luminescence glass/glass ceramics have W-LED application prospect and the great value for further study. |
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