From the perspective of the chromophore, 1,1,2,2-tetrakis­(4-(pyridin-4-yl)­phenyl)­ethane (TPPE) with the π-electron-rich tetraphenylethylene (TPE) and aggregation induced emission feature is selected as functional ligand to construct the fluorescent metal–organic frameworks. Three luminescent MOFs (1–3) have been successfully synthesized. Through combining 4,4′,4″-nitrilotrisbenzoic acid (H3TNB) with electron-donor triphenylamine (TPA), the highly porous pillared-layer compound 1 [Zn3(TPPE)1/2(TNB)2]­(4DMA·7H2O) was synthesized; interestingly, this MOF sensor film realizes the fast detection for nitrobenzene compounds with a response time of less than 3 min as well as good recyclability. Compound 2 [Zn7(TPPE)2(SO4 2–)7]­(DMF·H2O) exhibits the clear “turn-off” quenching responses for Cr2O7 2– in aqueous phase with high selectivity and sensitivity. Meanwhile, the fluorescent properties of compound 3 [Zn2(TPPE)3/2(NO3 –)­(OH–)­(H2O)]­(DMF·2H2O) were also investigated. Thus, these MOF materials could serve as the promising platform for luminescent sensing.

Three new three-dimensional (3D) porous Zn­(II)-based metal–organic frameworks (MOFs), namely, [Zn4O­(L)2(NMP)2(H2O)]·2NMP·2H2O (1), [Zn­(HL)­(bpe)0.5]·DMF·H2O (2), and [Zn­(HL)­(bipy)0.5]·DMF·H2O (3) [bpe = 1,2-di­(pyridin-4-yl)­ethene, and bipy = 4,4′-bipyridine], were successfully synthesized by 5′-carboxyl-(1,1′-3′,1″-terphenyl)-4,4″-dicarboxylic acid (H3L). Sing-crystal X-ray diffraction shows that complex 1 is a twofolded interpenetrated 3D framework possessing the [Zn4O­(COO)6] secondary building units (SBUs), and complexes 2 and 3 are two 3D isostructural networks with different N-donor ancillary ligands, where the partly deprotonated HL2– ligands are included. Gas adsorption behaviors of 1 to 3 for N2, CH4, and CO2 have been studied in detail at different temperatures, indicating that the high uptake and selectivity for CO2 will make it as potential gas storage and separation materials. Significantly, complexes 2 and 3 also exhibit the good organic dye selection and adsorption capacity, and the Congo red (CR) and methylene blue (MB) can be separated successfully by 2 in a very short time.

A super-stable multifunctional terbium(iii)-organic framework, namely {[Tb(TATAB) (HO)]·NMP·HO} (Tb-MOF, HTATAB = 4,4',4''-s-triazine-1,3,5-triyltri-m-aminobenzoic acid, NMP = N-methyl-2-pyrrolidone) was synthesized. Tb-MOF exhibits a 2D sql structure with binuclear [Tb(COO)(HO)] units as 4-connected nodes, and free water and NMP molecules are inserted between 2D layers through hydrogen-bonding interactions, forming a sandwich-type architecture. Observably, such a framework remains intact in a remarkable variety of environments such as common solvents and aqueous solutions with metal cations and inorganic anions, as well as with a pH ranging from 1 to 13. In particular, Tb-MOF can not only detect small organic molecules, metal cations and inorganic anions with high sensitivity and high selectivity, but also can accurately detect explosive 2-nitrophenol, 3-nitrophenol, 4-nitrophenol and 2,4,6-trinitrophenol in water. Its luminescence quenching response to Fe and CrO ions can be explained in terms of the competitive absorption mechanism. In addition, the luminescence intensity of Tb-MOF is strongly correlated with the pH value in a pH range from 1 to 13. Thus, this material can be potentially used as a multi-responsive luminescent sensor.