12CaO·7Al_2O_3∶Ce~(3+)透明陶瓷的制备及其闪烁特性研究

采用高温固相法制备了不同Ce3+掺杂浓度的12Ca O·7Al2O3(C12A7∶x%Ce3+)陶瓷样品。在350 nm紫外光激发下,样品的发射光谱呈现为主峰位于440 nm的宽带,来源于Ce3+的5d1→2F5/2和2F7/2的辐射跃迁。随着Ce3+掺杂浓度的增加,发射强度增大;当Ce3+摩尔分数超过0.7%时,有杂质相出现。为了进一步提高光致发光强度,采用自蔓延燃烧法合成了C12A7∶0.5%Ce3+陶瓷样品。在H2气氛下热处理,通过改变笼中阴离子基团的种类和数目提高了陶瓷闪烁特性(发光强度和衰减时间)。结果表明,C12A7∶Ce3+陶瓷是可应用于闪烁体的潜在材料。

Synthesis and Scintillation Properties of 12CaO·7Al2 O3:Ce3+ Transparent Ceramics

12CaO·7Al₂O₃:Ce³⁺ (C12A7:x%Ce³⁺) transparent ceramics were synthesized by a solid state method. Upon 350 nm UV excitation, a broad emission band located around 440 nm can be observed and it can be attributed to the transitions from 5d¹ to ²F_5/2 and ²F_7/2 of Ce³⁺, respectively. It can be seen that the emitting intensity increases with the increasing of Ce³⁺ doping concentration. When the mole fraction of Ce³⁺ exceeds 0.7%, other impurities appear. To enhance the emitting intensity, C12A7:0.5%Ce³⁺ transparent ceramics were prepared by a self-propagating combustion method. For the samples annealed in H₂ ambient, the scintillation properties, such as the emitting intensity and decay time, are improved by controlling sorts and amounts of encaged anions in C12A7. The experiment results show that Ce³⁺ doped C12A7 might be a potential scintillation material.