Guo Jingyuan, Jian Chenxi, Zeng Caixing, Xiong Zhengye, Wang Luyan, Zhou Dongcui
School of Electronic and Information Engineering, Guangdong Ocean University Zhanjiang 524088 China
Faculty of Chemistry and Environment Science, Guangdong Ocean University Zhanjiang 524088 China.
RSC Adv. 2023 Feb 8;13(8):4949-4957. doi: 10.1039/d2ra07109f. eCollection 2023 Feb 6.
Olivine-type phosphate LiMgPO doped with rare earth elements is considered a novel dosimetric material with excellent performance that is suitable for thermoluminescence (TL) and optically stimulated luminescence (OSL) measurements. Novel LiMgPO:Tm,Er samples were synthesized by a high-temperature solid-state reaction method. A detailed study of the TL and OSL of the samples was performed using β-ray irradiation and X-ray-excited optical luminescence (XEOL) spectroscopy. Density functional theory (DFT) calculations were performed to predict the preferential positions of thulium and erbium, and photoluminescence (PL) spectra and TL 3D spectra were analyzed. The DFT calculation results show that Mg is preferentially replaced by Tm/Er in the LiMgPO system. The PL/TL3D/XEOL spectra of the samples are dominated by the characteristic luminescence of Tm, and the OSL decay curve of photoluminescence has fast and slow decay components with decay constants of 5 s and 42 s, respectively. The TL and XEOL results show that LiMgPO:Tm,Er has strong emission signals under different types of radiation rays. The PL/TL3D/XEOL spectral results show that Er has no radiative excitation, but Tm has strong luminescence, such that the sample still emits strong TL and PL signals. Two TL emission peaks occur at approximately 120 °C and 300 °C, where the high-temperature peak is significantly more intense than the low-temperature peak, promoting the stability of the TL and OSL signals of the samples. The TL curve consists of 6 general TL dynamic peaks. The nonlinear parameters of the TL dose response are = 0.08 and = 479 Gy, and the OSL dose response is linear in the range of 0.2-1000 Gy. The TL and OSL signals of the LiMgPO:Tm,Er phosphor have good repeatability. Therefore, the LiMgPO:Tm,Er phosphor can be used for radiation dose measurement.
掺杂稀土元素的橄榄石型磷酸盐LiMgPO被认为是一种性能优异的新型剂量材料，适用于热释光（TL）和光激发发光（OSL）测量。采用高温固相反应法合成了新型LiMgPO:Tm,Er样品。利用β射线辐照和X射线激发光致发光（XEOL）光谱对样品的TL和OSL进行了详细研究。进行了密度泛函理论（DFT）计算以预测铥和铒的优先位置，并分析了光致发光（PL）光谱和TL三维光谱。DFT计算结果表明，在LiMgPO体系中Mg优先被Tm/Er取代。样品的PL/TL3D/XEOL光谱以Tm的特征发光为主，光致发光的OSL衰减曲线有快、慢衰减成分，衰减常数分别为5 s和42 s。TL和XEOL结果表明，LiMgPO:Tm,Er在不同类型的辐射射线作用下具有较强的发射信号。PL/TL3D/XEOL光谱结果表明，Er没有辐射激发，但Tm有较强的发光，使得样品仍能发出较强的TL和PL信号。两个TL发射峰分别出现在约120℃和300℃处，其中高温峰明显比低温峰强，提高了样品TL和OSL信号的稳定性。TL曲线由6个一般的TL动态峰组成。TL剂量响应的非线性参数为 = 0.08和 = 479 Gy，OSL剂量响应在0.2 - 1000 Gy范围内呈线性。LiMgPO:Tm,Er荧光粉的TL和OSL信号具有良好的重复性。因此，LiMgPO:Tm,Er荧光粉可用于辐射剂量测量。
