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The low-energy ultraviolet or visible photons can be produced by the interaction between the scintillator materials and ionizing radiation. For this reason, scintillator materials are widely used as radiation detectors, which are prevalently utilized in different applications such as nuclear medicine imaging, homeland security, high-energy physics, oil drilling explorations, etc. Herein, a high-atomic-number (Z) zirconium-based metal-organic framework nanoflower material CJLU-1 (Zr 6 (μ 3 -O) 4 (μ 3 -OH) 4 (OH) 6 (TCA) 2 (H 2 O) 6) (H 3 TCA = tri-carboxylic acids 4,4′,4″-nitrilotribenzoic acid) was synthesized and can effectively convert X-ray into visible light. CJLU-1 is composed of secondary structural unit hexagonal Zr metal cluster and connected by TCA ligands. The photo luminescence spectra (PL) emission peak and excitation peak of CJLU-1 are at 470 nm and 395 nm respectively. CJLU-1 exhibited radioluminescence (RL) peak with a maximum at 480 nm under steady-state excitation with X-rays. Moreover, by accommodating different guest molecules such as xylene and RhB in the same MOF material, intensity-tunable X-ray scintillation can be facilely achieved, providing a new class of scintillating materials with luminescence intensity tunability. The high-Z hexagonal Zr clusters, which are arranged in an orderly fashion, absorb and interact with the ionizing radiation and sensitize the adjacent organic ligands TCA to produce efficient RL. This work contributes to the development of high-Z zirconium-based MOFs and RL intensity-tunable scintillation materials towards future practical nuclear sensing applications. A high-atomic-number (Z) zirconium-based metal-organic framework nanoflower material CJLU-1 was synthesized and can effectively convert X-ray into visible light. [Display omitted] • A zirconium-based MOF was constructed and realized tunable radioluminescence upon accommodation of guest molecules. [ABSTRACT FROM AUTHOR]

Two similar N-Oxide-functionalized pillared Cd(II) metal-organic frameworks (MOFs), {[Cd(dpdcdo)(bpe) 0.5 (H 2 O)]·DMF·H 2 O} n (1) and {[Cd(dpdcdo)(bpe) 0.5 (H 2 O)]·DMA} n (2) [DMF ​= ​N,N-dimethylformamide, DMA ​= ​N,N-dimethylacetamide], have been obtained based on axially chiral 2,2′-dipyridine-3,3′-dicarboxylate-1,1′-dioxide (H 2 dpdcdo) ligand and rigid trans -1,2-bis(4-pyridyl)ethene (bpe) pillar. The N-Oxide group decorated in the channel of the Cd(II)-MOFs could provide effective "open donor sites" to enhance their affinity toward CO 2 molecule. The gas adsorption properties of the Cd(II) framework have been investigated by N 2 , H 2 , CH 4 , and CO 2 gases, and it reveals good CO 2 uptake, CO 2 sorption affinity, and sorption selectivity of CO 2 over CH 4 at ambient temperature. In addition, the solid-state luminescence properties of MOFs 1 and 2 have been conducted at room temperature, and they exhibit luminescent emission upon H 2 dpdcdo ligand. Two similar 3D pillared porous Cd(II) metal−organic frameworks with 1D channels have been synthesized based on an axially chiral N-Oxide functional carboxyl ligand. The gas adsorption behaviors exhibit good CO 2 selectivity over CH 4. The luminescent behaviors display emission upon the N-Oxide functional ligand. [Display omitted] • The pyridine-N-Oxide functional ligand possess superior characteristics than pyridine-N ligand. • Two similar 3D pillared porous Cd(II) MOFs possess 1D channels with N-Oxide donor sites and carboxylic O sites. • The gas adsorption behaviors show good capacity and selectivity for CO 2 over CH 4. • The luminescence behaviors display emission upon the N-Oxide functional ligand. [ABSTRACT FROM AUTHOR]