1 research outputs found
Multidimensional (0D to 3D) Alkaline-Earth Metal Diphosphonates: Synthesis, Structural Diversity, and Luminescence Properties
No full textA series
of new alkaline-earth metal diphosphonate frameworks were successfully
synthesized under solvothermal reaction condition (160 °C, 3
d) using 1-hydroxyethylidene-1,1-diphosphonic acid (CH<sub>3</sub>CÂ(OH)Â(H<sub>2</sub>PO<sub>3</sub>)<sub>2</sub>, hedpH<sub>4</sub>) as a diphosphonate building block and MgÂ(II), CaÂ(II), SrÂ(II), or
BaÂ(II) ions as alkaline-earth metal ion centers in water, dimethylformamide,
and/or EtOH media. These diphosphonate frameworks, (H<sub>2</sub>NMe<sub>2</sub>)<sub>4</sub>Â[MgÂ(hedpH<sub>2</sub>)<sub>3</sub>]·3H<sub>2</sub>O (<b>1</b>), (H<sub>2</sub>NMe<sub>2</sub>)<sub>2</sub>Â[CaÂ(hedpH<sub>2</sub>)<sub>2</sub>] (<b>2</b>), (H<sub>2</sub>NMe<sub>2</sub>)<sub>2</sub>Â[Sr<sub>3</sub>(hedpH<sub>2</sub>)<sub>4</sub>Â(H<sub>2</sub>O)<sub>2</sub>] (<b>3</b>), and [Ba<sub>3</sub>(hedpH<sub>2</sub>)<sub>3</sub>]·H<sub>2</sub>O (<b>4</b>) exhibited interesting structural topologies
(zero-, one-, two-, and three-dimensional (0D, 1D, 2D, and 3D, respectively)),
which are mainly depending on the metal ions and the solvents used
in the synthesis. The single-crystal analysis of these newly synthesized
compounds revealed that <b>1</b> was a 0D molecule, <b>2</b> has 1D chains, <b>3</b> was a 3D molecule, and <b>4</b> has 2D layers. All compounds were further characterized using thermogravimetric
analysis, solid-state <sup>31</sup>P NMR, powder X-ray diffraction
analysis, UV–vis spectra, and infrared spectroscopy. In addition,
EuÂ(III)- and TbÂ(III)-doped compounds of <b>1</b>–<b>4</b>, namely, (H<sub>2</sub>NMe<sub>2</sub>)<sub>4</sub>Â[Ln<sub><i>x</i></sub>Mg<sub>1–<i>x</i></sub>(hedpH<sub>2</sub>)<sub>2</sub>Â(hedpH<sub>2–<i>x</i></sub>)]·3H<sub>2</sub>O (<b>1Ln</b>), (H<sub>2</sub>NMe<sub>2</sub>)<sub>2</sub>Â[Ln<sub><i>x</i></sub>Ca<sub>1–<i>x</i></sub>(hedpH<sub>2</sub>)Â(hedpH<sub>2–<i>x</i></sub>)] (<b>2Ln</b>), (H<sub>2</sub>NMe<sub>2</sub>)<sub>2</sub>[Ln<sub><i>x</i></sub>Sr<sub>3–<i>x</i></sub>(hedpH<sub>2</sub>)<sub>3</sub>(hedpH<sub>2–<i>x</i></sub>)Â(H<sub>2</sub>O)<sub>2</sub>] (<b>3Ln</b>), and [Ln<sub><i>x</i></sub>Ba<sub>3–<i>x</i></sub>(hedpH<sub>2</sub>)<sub>2</sub>Â(hedpH<sub>2–<i>x</i></sub>)]·H<sub>2</sub>O (<b>4Ln</b>) (where
Ln = Eu, Tb), were synthesized, and their photoluminescence properties
were studied. The quantum yield of <b>1Eu</b>–<b>4Eu</b> was measured with reference to commercial red phosphor, Y<sub>2</sub>O<sub>2</sub>S:Eu<sup>3+</sup> (YE), and the quantum yield of terbium-doped
compounds <b>1Tb</b>–<b>4Tb</b> was measured with
reference to commercial green-emitting phosphor CeMgAl<sub>10</sub>O<sub>17</sub>:Tb<sup>3+</sup>. Interestingly, the compound <b>2Eu</b> showed very high quantum yield of 92.2%, which is better
than that of the reference commercial red phosphor, YE (90.8%)
