Developing universal stimuli‐responsive materials capable of emitting a broad spectrum of colors is highly desirable. Herein, we deliberately grafted a conformation‐adaptable organic chromophore into the established coordination space of a flexible metal–organic framework (MOF). In terms of the coupled structural transformations and the space confinement, the chromophore in the MOF matrix underwent well‐regulated conformational changes under physical and chemical stimuli, simultaneously displaying thermo‐, piezo‐, and solvato‐fluoro‐chromism with color tunability over the visible range. Owing to the resilient nature and the reduced dimensionality of the selected coordination space, all three color modulations behaved in a sensitive and self‐reversible manner, each following a linear correlation of the emission maximum with stimulus. Single‐crystal X‐ray diffraction of the variable‐temperature structures and solvent‐inclusion crystals elucidated the intricate color varying mechanisms.

Lanthanide metal-organic frameworks (Ln-MOFs) are promising for luminescence detection of volatile organic compound (VOC) vapors, but usually suffer from the silent or quenched Ln 3 + emission. Herein, we report a new dual-emissive Eu-MOF composed of the coordinatively unsaturated Eu 9 clusters that afford abundant open metal sites to form a confined "binding pocket" to facilitate the preconcentration and recognition of VOCs. Single-crystal structural analyses reveal that specific analytes can replace the OH oscillators in the first coordination sphere of Eu 3 + and form a unique hydrogen-bonding second-sphere adduct tying adjacent Eu 9 clusters together to minimize their nonradiative vibrational decay. With the promoted Eu 3 + luminescence, the MOF realizes real-time in situ visual sensing of THF vapor (< 1 s) and shows a quantitative ratiometric response to the vapor pressure with a limit of detection down to 17.33 Pa. Also, it represents a topperforming ratiometric luminescent thermometer.

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Two penta-REIII encapsulated tetravacant Dawson selenotungstates [H2N­(CH3)2]10­H3[SeO4RE5­(H2O)7­(Se2W14O52)2]·40H2O (RE = Dy3+ (1), Gd3+ (2)) were prepared by a one-step assembly strategy under bench conditions. Notably, the penta-REIII-substituted [SeO4RE5­(H2O)7­(Se2W14O52)2]12– polyoxoanion consists of two equivalent tetravacant Dawson [Se2W14O52]12– fragments linked by a central penta-REIII {SeO4RE5(H2O)7} cluster through 16 lacunary oxygen atoms and four bridging oxygen atoms from two [Se2W14O52]12– fragments. Furthermore, a series of cetyltrimethylammonium bromide (CTABr) encapsulated 1@CTA nanomaterials were prepared by the microwave method by controlling different reaction times and temperatures. The effects of time and temperature on the morphologies of 1@CTA nanomaterials were characterized by SEM images, and 1@CTA-5min prepared at 80 °C has a relatively uniform size of about 190 nm. Moreover, the photoluminescence properties of 1 and 1@CTA nanomaterials were investigated systematically, indicating that 1@CTA-5min prepared at 80 °C exhibits the strongest emission due to its smallest size and high dispersion. The energy transfer from the ST fragments to Dy3+ ions in 1 and 1@CTA-5min were proved by time-resolved emission spectra (TRES) and the change in CIE coordinates with increasing time, and their energy transfer mechanism diagram was demonstrated.

Six organic−inorganic hybrid pyridine-4-carboxylate-decorated organotin (OT)−lanthanide (Ln) heterometallic antimotungstates 3+ (2), Pr 3+ (3), Nd 3+ (4), Sm 3+ (5), Eu 3+ (6); Hpca = isonicotinic acid] have been prepared with the help of the structuredirecting effect of the trivacant [B-α-SbW 9 O 33 ] 9− segment toward [(CH 3 ) 2 Sn] 2+ and Ln 3+ ions in an acidic water medium. The prominent architecture characteristic is that their structural units consist of a trivacant [B-β-SbW 9 O 33 ] 9− segment stabilized by three [Sn-(CH 3 ) 2 (H 2 O)] 2+ groups and a [Ln(H 2 O) 6 (pca)] 2+ cation, which are interconnected to propagate an intriguing two-dimensional (2D) network. For all we know, 1−6 stand for the first 2D OT−Ln heterometallic polyoxometalates. Furthermore, luminescence performances of solid-state 3−6 were deeply surveyed at ambient temperature. Energy migration from [B-β-SbW 9 O 33 ] 9− and pca − to Sm 3+ centers in 5 was also studied. Comparative studies demonstrate that the contribution of [B-β-SbW 9 O 33 ] 9− sensitizing the emission of Sm 3+ is prominently larger than that of pca − sensitizing the emission of Sm 3+ in the emission process of 5. Most interestingly, 6 as a fluorescence probe exhibits high selectability and sensitivity for recognizing Zn 2+ and Cu 2+ in water.