Two rht anionic metal–organic frameworks were synthesized. There are six [M(H₂O)₆]²⁺ ions held together by a super-strong H-bond and arranged in a regular octahedron in each medium cage. Dye adsorption studies revealed a rapid and selective adsorption of cationic dyes and the adsorbed dyes can be released in saturated NaCl aqueous solution.

We presented an effective and universal strategy for the improvement of luminophore’s solid-state emission, i.e., macrocyclization-induced emission enhancement (MIEE), by linking luminophores through C(sp³) bridges to give a macrocycle. Benzothiadiazole-based macrocycle (BT-LC) has been synthesized by a one-step condensation of the monomer 4,7-bis(2,4-dimethoxyphenyl)−2,1,3-benzothiadiazole (BT-M) with paraformaldehyde, catalyzed by Lewis acid. In comparison with the monomer, macrocycle BT-LC produces much more intense fluorescence in the solid state (Φ_PL = 99%) and exhibits better device performance in the application of OLEDs. Single-crystal analysis and theoretical simulations reveal that the monomer can return to the ground state through a minimum energy crossing point (MECP_S1/S0), resulting in the decrease of fluorescence efficiency. For the macrocycle, its inherent structural rigidity prohibits this non-radiative relaxation process and promotes the radiative relaxation, therefore emitting intense fluorescence. More significantly, MIEE strategy has good universality that several macrocycles with different luminophores also display emission improvement.

Viologen, as a type of strong electron acceptor, is prone to undergo electron transfer (ET) and change color under external stimuli. However, due to the easy aggregation of viologen molecules, they usually suffer from poor fluorescence emission in the condensed phase. Herein, a new viologen derivative of VioCl₂·2Cl (1²⁺·2Cl) was designed and synthesized, in which the fluorescence was enhanced by introducing Me‐β‐CD to weaken the interactions between viologen molecules. Then a viologen‐based host–guest supramolecule of 1²⁺@Me‐β‐CD was obtained by electrostatic interactions. Photo‐/chemo‐responded guest 1²⁺ supplies 1²⁺@Me‐β‐CD, a green and dark purple caused by intramolecular and intermolecular ET. Furthermore, 1²⁺@Me‐β‐CD displays an additional thermal responsive purple color. The triple chromic behaviors all exhibit excellent reversibility and cycling stability. As expected, 1²⁺@Me‐β‐CD exhibits strong photoluminescence (PL) in solid–liquid dual states, presenting an improved quantum yield (Φ) from 1²⁺ (Φ_s = 0.37%, Φ_l = 16.74%) to 1²⁺@Me‐β‐CD (Φ_s = 10.45%, Φ_l = 25.86%), and the fluorescence intensity can be dynamically modulated by light, heat, and acid/base vapors. The multi‐responsive chromism and tunable fluorescence of 1²⁺@Me‐β‐CD allow for potential applications in information security and smart windows.

A new porous metal–organic framework (MOF) {[Cu₄(OH)₂(tci)₂(bpy)₂]·11H₂O} (1) based on a tetranuclear copper cluster with intracluster antiferromagnetic interactions was synthesized. Quartz crystal microbalance (QCM) sensor studies reveal sensitive and selective sensing for small molecules.

An anionic sod-type zeolitic metal–organic framework [(CH₃)₂NH₂]₉{Tb₆(η⁶-TATAT)₄(H₂O)₁₂}·3Cl·DMA·7H₂O [1, H₆TATAT = 5,5′,5′′-(1,3,5-triazine-2,4,6-triyltriimino)tri-1,3-benzenedicarboxylic acid] has been synthesized by metal–ligand directed assembly of hexacarboxylic acid units and Tb³⁺ ions. Compound 1 with extra-large cavities can efficiently extract natural product anthocyanins from blackberries and release them rapidly into NaCl aqueous solution. And, the nature of the anionic framework makes it very sensitive to detect cationic methyl viologen (MV²⁺) with a detection limit as low as 1 × 10⁻⁸ M.

Electron-withdrawing/coordinating o-phenolacetyl-substituted viologen can act as a visual sensor for solvents, bases, and temperature in organic solvents. Due to chelating phenolacetyl groups, this viologen can coordinate to Fe(III), Cu(II), and ZnCl₂ in aqueous and DMF solutions. Interestingly, this viologen can respond to temperature, grind, and NH₃ vapor in its solid state. Stimuli response is visible, fast, and fully reversible in air at room temperature. The color change is attributed to the enolic and/or free radical structure. This is the most versatile chromic material that responds to chemical and physical stimuli in both solution and solid state.