Ji Jinyan, Qi Chao, Zhao Hongxia, Yan Xuewu, Chai Zhifang, Wang Shuao, Zheng Tao
Yangtze River Delta Research Institute, Northwestern Polytechnical University, Suzhou215400, People's Republic of China.
School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an710072, People's Republic of China.
Inorg Chem. 2022 Oct 24;61(42):16794-16804. doi: 10.1021/acs.inorgchem.2c02636. Epub 2022 Oct 10.
Regulating the porosity of metal phosphonate frameworks is still challenging, even though this is not an issue for carboxylate-based metal-organic frameworks (MOFs). Quaternary ammonium cations are common template reagents widely used for structure control. However, it is not successful for uranyl phosphonate frameworks (UPFs) because the large volume sizes of templates make it challenging to enter the channels constructed by phosphonate ligands with small pore sizes and low dimensions. In this work, three new porous three-dimensional UPFs were synthesized using the phosphonate ligand and template reagents with the same geometry, namely, (TEA)(UO)(TppmH)·2HO (), (TPA)(UO)(TppmH) (), and (TBA)(UO)(TppmH)(HO)·4HO (). The porosity of the UPFs in this work showed a positive relation with the sizes of the template ammonium cations. Thermogravimetric analysis and infrared and ultraviolet spectroscopy were performed. The variable-temperature fluorescence spectra of the three compounds showed that the fluorescence intensity has an excellent relation to temperature with a potential application as fluorescence temperature sensors.
尽管调节金属膦酸盐骨架的孔隙率对基于羧酸盐的金属有机骨架（MOF）来说并非难题，但目前仍是一项挑战。季铵阳离子是常用于结构控制的常见模板试剂。然而，对于铀酰膦酸盐骨架（UPF）来说这并不成功，因为模板的体积较大，难以进入由小孔径和低维度膦酸盐配体构建的通道。在这项工作中，使用具有相同几何形状的膦酸盐配体和模板试剂合成了三种新型多孔三维UPF，即(TEA)(UO)(TppmH)·2HO （）、(TPA)(UO)(TppmH) （）和(TBA)(UO)(TppmH)(HO)·4HO （）。这项工作中UPF的孔隙率与模板铵阳离子的大小呈正相关。进行了热重分析以及红外和紫外光谱分析。这三种化合物的变温荧光光谱表明，荧光强度与温度具有良好的关系，具有作为荧光温度传感器的潜在应用价值。
