人工晶体学报, 2023, 52 (12): 2161, 网络出版: 2024-01-03
LaBr3∶Ce,Sr闪烁晶体的生长及性能研究
Growth and Properties Study of LaBr3∶Ce,Sr Scintillation Crystal
闪烁晶体 坩埚下降法 X射线激发发射光谱 能量分辨率 封装 scintillation crystal LaBr3∶Ce,Sr LaBr3∶Ce,Sr vertical Bridgman method Xray excited emission spectra energy resolution encapsulation
摘要
采用自发成核坩埚下降法生长了直径25 mm的铈、锶共掺溴化镧(LaBr3∶5%Ce,x%Sr,简称LaBr3∶Ce,Sr,其中x=0.1、0.3、0.5,摩尔分数)闪烁晶体,测试对比了晶体的X射线激发发射光谱、透过光谱和脉冲高度谱等。结果表明,不同Sr2+掺杂浓度的LaBr3∶Ce,Sr晶体在X射线激发下的发射光谱波形基本一致,但相比未掺杂Sr2+的样品,发射峰的峰位发生了明显的红移,随着Sr2+掺杂浓度的增大,发射峰红移程度增大。不同Sr2+掺杂浓度的LaBr3∶Ce,Sr晶体在350~800 nm不存在明显的吸收峰,0.3%和0.5%Sr2+掺杂晶体的透过率有所降低。随着Sr2+掺杂浓度的增大,能量分辨率逐步提高,Sr2+掺杂浓度为0.5%时,LaBr3∶Ce,Sr晶体的能量分辨率最高,达2.99%@662 keV。对尺寸25 mm×25 mm的LaBr3∶Ce,0.5%Sr晶体进行了防潮封装,所得晶体封装件的能量分辨率为2.93%@662 keV。
Abstract
In this paper, 25 mm lanthanum bromide scintillation crystals with 5%Ce3+ and different Sr2+ doping concentrations (0.1%, 0.3%, 0.5% in molar ratio) were successfully grown by spontaneous nucleation vertical Bridgman method. Xray excited emission spectra, transmission spectra and pulse height spectra of these crystals were measured. Results show that, the emission spectra waveform of LaBr3∶Ce crystals with different Sr2+ doping concentrations is basically consistent under Xray excitation, and the emission peak shows a significant red shift compared with that of sample without Sr2+ doping. With the increase of Sr2+doping concentration, the emission peak of LaBr3∶Ce,Sr crystal shows a slight red shift. There is no obvious absorption peak range from 350 to 800 nm of LaBr3∶Ce,Sr crystals with different Sr2+ doping concentrations. Compared with LaBr3∶Ce crystals, transmittance of 0.3% and 0.5% Sr2+doped LaBr3∶Ce crystals decrease. In addition, with the increase of Sr2+doping concentration, the energy resolution of the crystal increases correspondingly. LaBr3∶Ce,0.5%Sr crystal has the highest energy resolution of 2.99%@662 keV. The energy resolution of the encapsulated LaBr3∶Ce,0.5%Sr crystal with size of 25 mm×25 mm is 2.93%@662 keV.
王海丽, 周南浩, 许婉芬, 张微, 李焕英, 韩加红, 陈建荣. LaBr3∶Ce,Sr闪烁晶体的生长及性能研究[J]. 人工晶体学报, 2023, 52(12): 2161. WANG Haili, ZHOU Nanhao, XU Wanfen, ZHANG Wei, LI Huanying, HAN Jiahong, CHEN Jianrong. Growth and Properties Study of LaBr3∶Ce,Sr Scintillation Crystal[J]. Journal of Synthetic Crystals, 2023, 52(12): 2161.