Mechanochromic fluorescence (MCF) materials are a sort of smart material whose photophysical properties are sensitive to mechanical stimulation, such as photoluminescence color, fluorescence quantum yield and emission lifetime.

We report the first example of an AIEgen (DPP-BO) with fluorescence-phosphorescence dual emission under mechanical stimulation. By carefully analyzing the crystal structure of DPP-BO, the efficient intermolecular and intramolecular interactions should account for its unique mechanoluminescence (ML) properties, especially the abnormal phosphorescence, as further confirmed by controlled experiments and theoretical calculations for the presence of ISC transitions. These results provide important information for understanding the complex ML process, possibly opening up a new way to study the inherent mechanism of ML by broadening the application of AIEgens.

Two crystalline polymorphs of TMPE (Cp-form and Cc-form) exhibit totally different mechanoluminescence properties.

Unlike normal ACQ-to-AIE conversion by the introduction of aromatic rotors accompanying the realization of a twisted conformation and a prolonged π-system, in this communication, the adjustment of the flexible chains can reach this point with the tunable packing modes while the original π-system core and related properties of the aromatic naphthalene diimide remain nearly unchanged, providing an alternative approach for the inhibition of unwanted π-π stacking.

By intelligent design, a new "turn-on" fluorescent probe (1-CN) was obtained based on the deprotection reaction of the dithioacetal promoted by Hg2+ ions, which could sense mercury ions sensitively and selectively, with the detection limit of 8×10(-7) M. Thanks to the apparent turn-on signal, 1-CN has been successfully applied to rapidly detect trace amounts of mercury ions as test strips and cell image.

In this paper, four new hyperbranched polytriazoles containing azo moieties, derived from different AB2‐type monomers, were successfully prepared through the “click” chemistry reaction under copper(I) catalysis by modifying the synthetic route. The polymers were soluble in organic solvents and exhibited good second‐order nonlinear optical (NLO) properties. Thanks to the self‐assembly of perfluoroaromatic moieties in the periphery, HP2 showed the best NLO properties, with the d33 value as high as 145.0 pm V−1.

As the hole-transporting layer fabricated through a facile solution process, DT2, bearing 22 triphenylamine moieties, can endow an Alq3 based multi-layer OLED device with a maximum current efficiency of 2.36 cd A−1.

Through a postfunctional method, a new disubstituted polyacetylene (P2) bearing cyclen moieties in the side chains, was prepared conveniently and exhibited strong green fluorescence. P2 showed good pH stability in the solution mixture of THF/H 2 O (v/v ¼ 1 : 1), and could report the presence of trace Cu 2+ ions at a concentration as low as 1.0 Â 10 À7 mol L À1 in diluted solutions, through an on-off mode. By utilizing the displacement strategy, due to the much higher stability constant of the complex of S 2À and Cu 2+ , the quenched fluorescence of P2 by Cu 2+ ions could recover upon the addition of trace S 2À anions, with a detection limit down to 2.0 Â 10 À7 mol L À1 . Excitingly, no interference was observed from other anions, including AcO À , SO 3 2À