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Considering that cyclotriphosphazene polycarboxylic acid is a kind of organic ligand with fantastic structures and performances and the unique luminescence characteristics of rare earth ions, a series of porous lanthanide metal–organic frameworks (Ln-MOFs) (CH3)2NH2[Ln3(HCPCP)1.5(CH3COO)]·6DMA (Ln = Ce (1), Sm (2), Eu (3), Tb (4), HCPCP = hexa(4-carboxyphenoxy)cyclotriphosphazene, and DMA = N,N-dimethylacetamide) were synthesized with novel topological network structures. Compound 4 exhibited a sensitive recognition of –NO2, and had a fluorescence quenching phenomenon for seven kinds of nitro aromatic compounds (NACs). In particular, it showed the best fluorescence response to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP), and the KSV values were 2.86 × 105 M−1 and 8.21 × 104 M−1, and the limit of detection (LOD) values were 0.20 μM and 0.71 μM, respectively. At the same time, we successfully doped different concentrations of Eu3+ into compound 4 to obtain a series of doped Ln-MOF materials x%Eu3+@4 (x = 0.5, 2.5, 5, 7.5, 10, 15 and 20). With the increase of Eu3+ doping ratios, the characteristic peaks of Tb3+ and Eu3+ changed regularly, and the energy transfer from Tb3+ to Eu3+ ions occurred. By changing the excitation wavelength of the samples with different Eu3+ doping concentrations, a higher quality white light emitting material 7.5%Eu3+@4 (λex = 340 nm) was finally obtained, with a CIE coordinate of (0.3268, 0.3212). [ABSTRACT FROM AUTHOR]

The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors. [ABSTRACT FROM AUTHOR]

A series of 4f-5f heteronuclear metallic complexes were synthesized by a hydrothermal route from mixtures of uranyl acetate, lanthanide nitrate, and 1,2,4,5-benzenetetracarboxylic acid (H4BTA) in an aqueous system. Single-crystal X-ray analysis revealed that the thirteen UO2-Ln-BTA complexes ([(UO2)1.5Ln(C10O8H2)1.5(H2O) x]⋅ y H2O; Ln=La ( 1), Ce ( 2), Pr ( 3), Nd ( 4), Sm ( 5), Eu ( 6), Gd ( 7), Tb ( 8), Dy ( 9), Ho ( 10), Er ( 11), Tm ( 12), Yb ( 13); x=6 for 1- 4, x=5 for 5- 13; y=0 for 4, y=1 for 3, y=2 for 2, y=3 for 5, 9, 10, 12, 13, y=4 for 1, 6, 7, 8, 11) are isomorphous with three-dimensional structures. For the purpose of developing potential applications of the UO2-Ln-BTA complexes, we investigated their surface photovoltage and photocatalytic properties. In addition, the thermogravimetric analysis and photoluminescent properties of these complexes were also studied in detail. [ABSTRACT FROM AUTHOR]

1 A new Ln-BTC-Ac-FM framework intelligent materials 2 High sensitivity and selectivity to UO 2 2+ in aqueous solution. 3 Better adsorption effects on Coomassie Brilliant Blue (CBB) and Eosin The unique fluorescence properties of rare earth ions and subtle interactions with organic ligands make the target lanthanide metal-organic frameworks show potential development prospects in many fields. Based on this situation, a series of new lanthanide metal-organic frameworks Ln-BTC-AC-FM: (CH 3) 2 NH 2 [Ln 2 (BTC)(AC) 3 (FM)], (Ln=Pr (1), Ce (2), Nd (3), Eu (4), Sm (5), Gd (6), Tb (7), Ho (8), Er (9) and Yb (10), H 3 BTC=1,3,5-benzenetricarboxylic acid) were synthesized through the reaction of triangular polycarboxylic acid ligand (H 3 BTC) and rare earth nitrate Ln(NO 3) 3 ·6H 2 O with mixed formic acid (FM) and glacial acetic acid (AC) system. Due to this new type of Ln-BTC-AC-FM MOFs have unique and excellent fluorescence properties, we selected (CH 3) 2 NH 2 [Eu 2 (BTC)(AC) 3 (FM)] (4) to explore its detection performance for UO 2 2+ in aqueous solution. The study found that 4 is a high-efficiency fluorescent probe, which has a good quenching effect on uranium solution, and the quenching rate can reach 98.01%. At the same time, 4 has a good fluorescent response to UO 2 2+, with a higher K SV value of 8.56 × 103 M−1 and a lower detection limit of 4.12 μM. In addition, we also studied the adsorption properties of this series of Ln-BTC-AC-FM MOFs for dyes because of their novel three-dimensional microporous structures. The results showed that 4 has a good adsorption effect on Coomassie Brilliant Blue (CBB) and Eosin. Moreover, it was found that the dye adsorption process was proved to be a suitable pseudo-second-order kinetic model. [Display omitted] [ABSTRACT FROM AUTHOR]