Studies On Preparation, Characterization And Luminescence Properties Of Rare Earth Coordination Polymers Luminescent Materials

During the past decades, lanthanide coordination polymers?CP? have attracted much more interests, owing to their varied topological structure and unique performance. Lanthanides with special features of the electronic 4f configurations exhibit outstanding luminescence properties. Then again, the distinctive emission properties of lanthanide complex, which contains long luminescence lifetime, sharp and easily recognizable emission bands, make it be suitable for applying in fluorescent probe, upconversion luminescence, cell imaging, bio-sensor and drug delivery. In recent years, we were devoted on the fabrication of lanthanide CP with excellent luminescence properties by using a perfluorinated linker. Herein, Yttrium-based coordination polymer hierarchical micro/nanostructures and terbium-based flowerlike coordination polymer have been successfully prepared by a simple hydrothermal route. Moreover, the luminescence properties of the as-prepared products have been investigated carefully and their applications were also explored. Meanwhile, the lanthanide coordination polymer single crystal has also been synthesized successfully at room temperature. The as-prepared products were further investigated by various measurement techniques. The main contents of this paper are as follows:?1? Fabrication of Yb³⁺-Er³⁺ co-doped yttrium-based coordination polymer hierarchical micro/nanostructures: upconversion luminescence property and its calcination to the corresponding oxideUniform Yb³⁺ and Er³⁺ co-doped yttrium-based coordination polymer?CP? hierarchical micro/nanostructures were successfully fabricated through a simple hydrothermal method with allantoin as the organic linker. Meanwhile, the products obtained at different reaction temperature and times were investigated carefully. Then the possible formation mechanism of the novel hierarchical micro/nanostructures was proposed. Moreover, the corresponding Y2O3: Yb³⁺, Er³⁺ hierarchical micro/nanostructures were obtained by annealing the CP at 800 oC for 4 h under ambient pressure. The upconversion luminescence of the precursors and the corresponding oxides was studied.?2? Hierarchically eurium-based coordination polymer flower-like: preparation and luminescence properties investigationHierarchically eurium-based coordination polymer?CP? flower-like were successfully synthesized via a facile hydrothermal route, among which 3,4,5,6-Tetrafluorophthalic acid?H2TFA? was used as organic linker. During the reaction, the morphologies of products were varied by controlling the reaction parameters?reaction time, solvent composition?. Based on the above experiments, a possibile growth mechanism was proposed. In addition, the luminescence properties of the eurium-based coordination polymer were systematically investigated.?3? Lanthanide CPs based on 3,4,5,6-Tetrafluorophthalic acid: crystal structure and luminescence propertiesA serious of single crystal, [Ln2?tfa?3?phen?2?H2O?2]?Ln = Tb, Eu, Gd? have been synthesized at room temperature, among which 3,4,5,6-Tetrafluorophthalic acid?H2TFA? was used as organic linker and 1,10-Phenanthroline monohydrate?phen? was used as ancillary ligand. Among these complexes, sample 2 is further characterized by single-crystal diffraction, it crystalizes in the triclinic space group P-1, with a = 14.1139?7? ?,b = 14.3166?7? ?,c = 15.0782?7? ?,? = 63.4210?10?°,?= 82.0360?10?°, ? = 65.4410?10?°, V = 12474.1?2? ?3,Z = 1. Moreover, the luminescence properties of powder sample 1 and 2 were investigated.?4? 1D lanthanide CPs fabricated by 3-methoxy-2,4,5-trifluorobenzoicacid: crystal structure and sensitive Trp sensorBased on a ligand which contains methoxy and fluorine groups, a series of isostructural lanthanide coordination polymers?CPs? [Ln?tfmba?₃?H₂O?]_n?Ln = Tb, Eu, Gd? are synthesized, and they are characterized by FT-IR EA, PXRD, TGA and luminescence. Among these complexes, sample 1 is further characterized by single-crystal diffraction, it crystalizes in the triclinic space group P-1, with a = 8.8577?8? ?,b = 12.0523?11? ?,c = 13.6494?13? ?,? = 114.2400?10?°,? = 96.3570?10?°,? = 96.6170?10?°,V = 1289.5?2? ?3,Z = 2. The luminescence properties of powder sample 1 and 2 were investigated at room temperature. In addition, the sensing property of sample 1 with tryptophan was systematically investigated.