Acta Chimica Sinica ›› 2012, Vol. 70 ›› Issue (13): 1496-1500.

Article

### 稀土亚磷酸盐GdxTb2-x(HPO3)3(H2O)2 (0≤x≤2)的微波合成、表征与性质研究

1. 吉林大学化学学院无机合成与制备化学国家重点实验室长春 130012
• 投稿日期:2012-04-10 发布日期:2012-05-08
• 通讯作者: 于吉红 E-mail:jihong@jlu.edu.cn
• 基金资助:

项目受国家自然科学基金(No. 20971053)和国家重大基础研究发展计划项目(No. 2011CB808703)资助.

### Microwave Synthesis, Characterization and Properties of Lanthanide Phosphites GdxTb2-x(HPO3)3(H2O)2(0≤x≤2)

Wang Xi, Han Yide, Hao Suqin, Yu Jihong, Xu Ruren

1. State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012
• Received:2012-04-10 Published:2012-05-08
• Supported by:

Project supported by the National Natural Science Foundation of China (No. 20971053) and the State Basic Research Project of China (No. 2011CB808703).

A family of novel lanthanide phosphites GdxTb2-x(HPO3)3(H2O)2 (0≤x≤2) were successfully synthesized by using the microwave irradiation synthesis method. In the synthetic procedure of Ln2(HPO3)3(H2O)2 (Ln＝Gd, Tb), the mixture of 15 mL solution of Ln(NO3)3 (0.2 mol/L), 0.12 g of H3PO3 and 300 μL of TMAOH was heated to 180 ℃ in 1 min in a microwave oven (Milestone ETHOS-D), and kept for 10 min at the same temperature. The Tb3+/Gd3+ mixed samples were prepared by introducing the desired Tb3+ and Gd3+ contents in the initial gel. They are isostructural confirmed by the powder X-ray diffraction analysis. The structure of Gd2(HPO3)3(H2O)2 was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic space group P21/c with a＝6.9124(6) Å, b＝12.8891(12) Å, c＝12.3692(11) Å, β＝100.1520(10)°. Its structure is comprised of GdOn (n＝7, 8) polyhedra that are linked via [HPO3] pseudo tetrahedra, giving rise to a 3D framework. The structure of Gd2(H2O)2(HPO3)3 is different from the compounds Pr2(H2O)2(HPO3)3 and La2(H2O)2(HPO3)3, which are built from Pr(La)O9 polyhedra connected with [HPO3] pseudo tetrahedral. The photoluminescent study of Gd2(HPO3)3(H2O)2 and Tb2(HPO3)3(H2O)2 show that they display the typical Gd3+ and Tb3+ photoluminescence, respectively. The excitation spectra monitored at the main 5D47F5 line (542 nm) of Tb3+ for the Tb3+/Gd3+ mixed samples display both characteristic Tb3+ and Gd3+ lines, which reveals the existence of Gd3+ to Tb3+ energy transfer. The emission spectra of Tb3+/Gd3+ mixed samples excited in the Gd3+ (273 nm) levels show the typical Tb3+ lines, also implying the occurrence of Gd3+-Tb3+ energy transfer. The intensity of 5D47F3 increases with increasing the content of Tb3+, which indicate that the Tb3+ doped gadolinium phosphites could be used as green color phosphors. The magnetic measurement of Gd2(HPO3)3(H2O)2 reveals that it exhibits very weak antiferromagnetic behavior and its experimental reciprocal susceptibility can be fitted by Curie-Weiss law at 4—300 K.