摘要 沸腾磷酸结晶制备的镧系磷酸盐 LnPO4·H2O(Ln:La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu 和 Y)的热分解特性已提出解决方案。根据对 DTA 和 DTG 曲线观察到的影响,当加热到 1000 °C 时,磷酸盐可分为两组:(a)第一组包括六方(La→Tb)和正交 Dy 磷酸盐,( b) 第二组由四方 (Ho→Lu) 和 Y 磷酸盐组成。组 (a) 的特征是两个低于 300 °C 的吸热线,与脱水有关,以及一个高于 700 °C 的放热线,与六方/斜方晶向单斜晶的转变有关。多晶型转变的温度随着镧系元素原子序数从 900 °C (Tb, Dy) 的增加而增加。(b)组在很宽的温度范围(100-600°C)内脱水,即使在 950°C 加热后仍保持四方晶体结构。然而,增加的结晶度、a 轴和 c 轴的收缩以及 IR 光谱的差异表明 (Ho→Lu)
HDEHP assisted solvothermal synthesis of monodispersed REPO<sub>4</sub> (RE = La–Lu, Y) nanocrystals and their photoluminescence properties
作者:Zhen Yang、Guangzhen Yuan、Xiannan Duan、Shuai Liang、Guoxin Sun
DOI:10.1039/c9nj05829j
日期:——
In this paper, a novel method is reported for the preparation of spherical REPO4 particles.
在这篇论文中,报道了一种新颖的方法,用于制备球形REPO4颗粒。
Synthesis of Metal Phosphates Using SiP2O7
作者:Carlos E. Bamberger、George M. Begun、Dale E. Heatherly
DOI:10.1111/j.1151-2916.1983.tb10575.x
日期:1983.11
The reaction of SiP/sub 2/O/sub 7/ with rare-earth fluorides and oxides and with UO/sub2/ proceeds at high temperatures (1000/sup 0/ to 1200/sup 0/C) to convert the rare-earth and uranium compounds to ortho- or pyro-phosphates. In these reactions between intimately mixed powders, very finely segregated SiO/sub2/ is formed and distributed throughout the phosphates. This procedure may be useful for
Systematic Synthesis and Characterization of Single-Crystal Lanthanide Orthophosphate Nanowires
作者:Yue-Ping Fang、An-Wu Xu、Rui-Qi Song、Hua-Xin Zhang、Li-Ping You、Jimmy C. Yu、Han-Qin Liu
DOI:10.1021/ja037280d
日期:2003.12.1
systematic synthesis of lanthanide orthophosphate crystals with different crystalline phases and morphologies. It has been shown that pure LnPO(4) compounds change structure with decreasing Ln ionic radius: i.e., the orthophosphates from Ho to Lu as well as Y exist only in the tetragonal zircon (xenotime) structure, while the orthophosphates from La to Dy exist in the hexagonal structure under hydrothermal
已经开发了一种简单的水热法用于系统合成具有不同晶相和形态的镧系元素正磷酸盐晶体。已经表明纯 LnPO(4) 化合物随着 Ln 离子半径的减小而改变结构:即,从 Ho 到 Lu 以及 Y 的正磷酸盐仅存在于四方锆石(磷钇矿)结构中,而从 La 到 Dy 的正磷酸盐存在在水热处理下的六方结构中。获得的六方结构镧系元素正磷酸盐 LnPO(4)(Ln = La、Ce、Pr、Nd、Sm、Eu、Gd、Tb 和 Dy)产品具有线状形态。相比之下,在相同实验条件下制备的四方 LnPO(4)(Ln = Ho、Er、Tm、Yb、Lu、Y)样品由纳米颗粒组成。得到的六边形LnPO(4) (Ln = La --> Tb)可以转化为单斜独居石结构产物,在空气中900℃煅烧后形貌保持不变(六方DyPO(4)是特例,经煅烧转变为四方DyPO(4)),而(Ho--> Lu, Y)PO(4) 的四方结构通过煅烧保持不变。由此产生的
The conditions of formation of complex lanthanide chromate(VI)-phosphates K2R(CrO4)(PO4) were found and these compounds were synthesized by solid-state synthesis with variation of the starting compounds, the temperature of synthesis (500–800 °C), and the annealing time (6–200 h). These salts are typical of late lanthanides, R = Dy-Lu, Y. Using lutetium derivatives as examples, it was shown that no similar compounds with lithium or sodium are formed. All the complex chromate(VI)-phosphates obtained decompose under static conditions at temperatures above 550 °C. They are isostructural and crystallize in the monoclinic system. The unit cell parameters for thulium, ytterbium, and lutetium compounds were calculated. It is shown by IR spectroscopy that PO4 tetrahedra in the crystal lattice of potassium lanthanide chromate(VI)-phosphates are substantially distorted, whereas the CrO4 tetrahedra retain the regular tetrahedron symmetry (T d ).
Facile Synthesis of Monodisperse LuPO<SUB>4</SUB>:Eu<SUP>3+</SUP>/Tb<SUP>3+</SUP> Hollow Nanospheres and Their Luminescence Properties
Highly uniform and well-dispersed LuPO4 hollow nanospheres were successfully synthesized via a facile solution-phase method by utilizing the colloidal spheres of Lu(OH)CO3 as a sacrificial template and NH4H2PO4 as a phosphorus source. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FT-IR), photoluminescence (PL) spectra, and cathodoluminescence (CL) spectra were employed to characterize the samples. The result indicates that the hollow LuPO4 spheres can be indexed to the tetragonal phase. The hollow LuPO4 spheres with diameter of about 300 nm become larger with respect to the sacrificial template. The shell of the hollow microspheres consists of numerous nanorods with the thickness of approximately 10 nm. Moreover, the possible formation mechanism of the evolution from Lu(OH)CO3 spheres to the final hollow LuPO4 hollow spheres has been proposed. In addition, upom ultraviolet (UV) and low-voltage electron beams excitation, 5 mol% Eu3+ and 5 mol% Tb3+ doped LuPO4 samples exhibit strong orange–red and green emission, corresponding to the characteristic lines of Eu3+ and Tb3+ under UV excitation, respectively, which may find potential application in the fields of color display and biomedicine.