CAJ | 학술논문

在硫酸盐掺入稀土元素的研究中,得到了几种掺入Eu2+的碱土金属硫酸盐磷光体M SO4：Eu2+(M =Mg, Ca, Sr, Ba),这组磷光体具有与掺入三价稀土离子(Tm3+, Dy3+, Eu3+)的碱土金属硫酸盐截然不同的热释光特性,热释光三维发光谱中只呈现一个热释光峰,对γ和β辐射的热释光剂量响应为线性-亚线性响应。结果清楚地显现出Eu2+对碱土金属阳离子的等价取代而形成的等电子陷阱对这些磷光体的热释光特性起了关键性的作用, Eu2+等电子陷阱与基质中的本征缺陷SO42?形成的缺陷复合体作为热释光多阶段过程的基本作用单元,基本上产生一次作用热释光事件。 SrSO4：Eu2+是一种典型的等电子陷阱发光的磷光体,它具有相当高的热释光和光释光发光效率。
재류산염참입희토원소적연구중,득도료궤충참입Eu2+적감토금속류산염린광체M SO4：Eu2+(M =Mg, Ca, Sr, Ba),저조린광체구유여참입삼개희토리자(Tm3+, Dy3+, Eu3+)적감토금속류산염절연불동적열석광특성,열석광삼유발광보중지정현일개열석광봉,대γ화β복사적열석광제량향응위선성-아선성향응。결과청초지현현출Eu2+대감토금속양리자적등개취대이형성적등전자함정대저사린광체적열석광특성기료관건성적작용, Eu2+등전자함정여기질중적본정결함SO42?형성적결함복합체작위열석광다계단과정적기본작용단원,기본상산생일차작용열석광사건。 SrSO4：Eu2+시일충전형적등전자함정발광적린광체,타구유상당고적열석광화광석광발광효솔。
A series of alkaline earth sulphate phosphors M SO4:Eu2+(M =Mg, Ca, Sr, Ba) is obtained in doping experiments. It is discovered that these phosphors doped with Eu2+ ions have the thermoluminescence (TL) characteristics which are quite different from those in the alkaline earth sulphate phosphors doped with trivalent rare earth ions RE3+ (RE =Dy, Tm, Eu). It is also observed that there is only one glow peak in the three-dimensional emission spectrum and the radiation dose response of the glow peak is linear-sublinear in the series of phosphors M SO4:Eu2+ (M = Mg, Ca, Sr, Ba). However, quite a lot of experimental results show that there are several glow peaks in the three-dimensional emission spectrum, and the TL radiation dose responses are linear-supralinear in the series of phosphors MSO4:RE3+(M =Mg, Ca, Sr, Ba and RE=Dy, Tm, Eu). The reason lies in the structures of defect complexes which are formed in the course of preparation of these phosphors and include intrinsic imperfects and dopants. These defect complexes can be regarded as basic elements in the TL multi-stage process. In the series of phosphors M SO4:Eu2+ (M =Mg, Ca, Sr, Ba), the isoelectronic traps produced by doping Eu2+ ions which have the same valences as superseded alkaline earth ions are very localized traps to form the defect complexes (Eu2+ isoelectronic trap-SO2?4 ) that are basic elements in the TL multi-stage process, in which there are one-hit TL events basically. However, in the MSO4:RE3+ (M =Mg, Ca, Sr, Ba) phosphors, the defect complexes (RE3+-SO2?4 -cation vacancy VM ) are basic elements in the TL multi-stage process, in which there are two-hit TL events basically. It is clear that the Eu2+ isoelectronic trap phosphors play key roles in TL Characteristics in M SO4:Eu2+ (M = Mg, Ca, Sr, Ba). In addition, it has been observed that the wave length at the single TL peak in each of the three-dimensional emission spectra of the series of phosphors M SO4:Eu2+ (M =Mg, Ca, Sr, Ba) is related to the substrate of each of these phosphors, such as the wave lengths at the TL peaks are 440, 385, 375 and 375 nm for MgSO4:Eu2+, CaSO4:Eu2+, SrSO4:Eu2+, and BaSO4:Eu2+ respectively. The experimental results display the characteristics of Eu2+ isoelectronic traps formed by substituting alkaline earth ions which have different cationic radii and electronegativities. The SrSO4:Eu2+ phosphor can be called typical isoelectronic trap phosphor which has the higher TL and optical stimulated luminescence e?ciency.