Dy或Tb掺杂的MgB4O7磷光体的热释光特性

用高温固相反应法研制了MgB₄O₇:Dy和MgB₄O₇:Tb两种热释光材料.用自制的三维热释光谱仪测量了两种磷光体的三维发光谱,从MgB₄O₇:Dy磷光体的三维发光谱观察到:1.热释光发光峰峰温为220,380℃;2.Dy³⁺离子的发光波长为480,575,660nm;3.220,380℃发光峰的相对强度随高温固相反应温度的升高而变化,但发光峰温和波长基本保持不变.由MgB₄O₇:Tb磷光体的三维发光谱可看到在230,340,420℃附近有三个发光峰,发光谱线波长分别为489,543,589,620nm.不同的高温烧结温度不仅对发光峰的发光强度有很大影响,而且还对Tb³⁺发光谱形产生影响,当温度高于850℃时Tb³⁺离子发光谱线开始变成了发光谱带.此外,对比MgB₄O₇:Dy和MgB₄O₇:Tb两种热释光材料的二、三维发光谱,得出了掺入三价稀土离子的热释光材料的发光峰峰温主要由基质材料决定,发光波长则取决于稀土离子的4f电子能级间的跃迁.

Thermoluminescence Characteristics of MgB4O7 Doped with Dy or Tb

Two thermoluminescence(TL)materials MgB₄O₇:Dy and MgB₄O₇:Tb were synthesized under the condition of high temperature.The 3-dimensional(3D)TL spectra of two materials were measured by the 3D TL spectrometer made in the laboratory.From the 3D TL spectra of MgB₄O₇:Dy,we can conclude:there are two TL glow peaks at about 220 and 380℃ and the wavelengths of the TL emission spectra are 480,575,660 nm.The intensity ratio of glow peak at about 220℃ to that at 380℃ can be raised gradually by high temperature treatment.However,the temperature and wavelength of the glow peaks have no obvious change.From the 3D spectra of MgB₄O₇:Tb,we can conclude:there are three TL peaks at about 230,360 and 420℃ and the wavelengths of the TL emission spectra is 489,543,589,620 nm.Different sintered temperature affects not only the TL sensitivity of MgB₄O₇:Tb,but also the spectral shape of the 3D TL spectra.When the temperature is higher than 850℃,the spectral line of Tb³⁺ turns to the spectral band.By comparing the TL glow curve and emission spectra between MgB₄O₇:Dy and MgB₄O₇:Tb,we can conclude that in the TL material doped with trivalence rare earth ions,the temperature of the glow peak is mainly decided by the host and the emission wavelength of the glow peak is mainly due to the transition of the energy level of the rare earth ions.