Yb3＋/Tm3＋共掺杂BST铁电厚膜的制备及其上转换发光∗

摘要

The Yb3+/Tm3+ co-doped BST thick films were prepared by screen printing process on alumina sub-strates.The effect of rare earth ions doping on the microstructure and photoluminescence properties were inves-tigated.It was found that Tm3+ and Yb3+ ions substituted for B site ions when the concentration was small.The RE ions can substitute both A site and B site with increasing RE ions concentration.The PL spectra of the Yb, Tm co-doped BST thick films were measured with 800 nm excitation source at room temperature.The 468 nm blue up-conversion luminescence was assigned to 1 G4→3 H6 transition of the Tm3+,and the 533 nm green up-conversion luminescence was assigned to 1 D2→3 F4 transition of the Tm3+ with the sensitization of Yb3+.The in-tensity of the 468 nm luminescence peeks first became stronger then decreased as increasing the ratio of the Yb3+ and Tm3+,the luminescence intensity reached the maximum at the ratio of 2∶1 for Yb3+ and Tm3+.The mechanism of indirect up-conversion luminescence was also studied.%利用丝网印刷工艺制备出稀土 Yb3＋/Tm3＋共掺杂的 Ba0．8 Sr0．2 TiO3铁电陶瓷厚膜，利用 XRD、SEM、EDS、Raman和荧光光谱仪研究了稀土掺杂对厚膜微结构和发光性能的影响.实验发现，在低掺杂量时Yb3＋、Tm3＋离子在BST晶格中首先替代B位离子，高掺杂量时则同时占据 A位和B位离子.掺杂后的厚膜仍表现为典型的铁电四方相结构.在800 nm近红外激光激发下，共掺杂的 BST 厚膜中的 Tm3＋离子通过Yb3＋离子的敏化作用在468与533 nm处实现了间接上转换蓝色与绿色荧光输出，分别对应于Tm3＋离子的1 G4→3 H6跃迁和1 D2→3 F4跃迁.468 nm蓝色荧光强度随着 Yb3＋、Tm3＋离子比的增加先增强后减弱，在 Yb3＋、Tm3＋离子共掺比为2∶1达到最大，并对上转换发光的机理进行了分析.