采用高温固相法制备了MgB407:Tm,Mn磷光体材料,测量了热释光发光曲线和热释光三维光谱以及剂量响应曲线。其主发光峰温度约为400℃,发光波长455rim。MgB407:Tm,Mn主发光峰面积比LiF:Mg,Ti高6.2倍,具有很好的热稳定性,在0.1-2000Gy范围内具有良好的线性.超线性剂量响应。
Background: The interest on magnesium borate TL materials has arisen because of their dosimetric properties, such as good tissue equivalent, linear dose response. Many studies on various magnesium borate phosphors doped with one or two rare earth dopants showed that these dopants play key roles in the TL process. Purpose: This paper attempts to study the TL characteristics and mechanisms of MgB407:Tm,Mn phosphors. Methods: The phosphors were prepared by high temperature solid reaction method, and measured by TL reader and three dimension TL spectrometer. Results: The experiment results show that the TL sensitivity of MgB407:Tm,Mn phosphor is about 6.2 times higher than that of LiF:Mg,Ti, and the MgBnOT:Tm,Mn has good thermo stability because of its high temperature of TL peak. Moreover, the TL dose dependence curves were observed to be almost linear in the range of 0.1 Gy to 2 kGy. The TL emission spectrum show that the main glow peak is located at 400℃ in wavelength 455 nm. Conclusions: There is competition in the luminescence processes between Tm3+ luminescence centres and Mn activators and probable energy transfer may occur from Mn2+ to Tm3+. The MgBnO7:Tm, Mn may be a good candidate of TL phosphor in dosimetry at high temperature condition.