Jinbo Ouyang

Stimuli‐responsive materials capable of dynamically tuning their optical outputs promise new architectures for smart photonics, yet simultaneously achieving rapid response kinetics and low loss optical waveguiding within a single crystal phase remains challenging. Here, we present two Excited‐state intramolecular proton transfer (ESIPT) active Schiff base crystals where supramolecular hydrogen bonding engineering resolves this trade‐off. By strategically introducing intermolecular hydrogen bonding networks alongside intrinsic intramolecular proton transfer channels, these crystals deliver highly sensitive, fully reversible thermofluorochromic switching coupled with efficient waveguiding performance. Single‐crystal X‐ray diffraction and theoretical calculations reveal that the subtle interplay between molecular conformation and supramolecular packing topology governs both the thermal emission color gradation and the quenching dynamics. Leveraging these dual photonic functions, we demonstrate a multilevel anti‐counterfeiting platform that pairs static visual features with dynamic thermal responsiveness. Overall, this work highlights the potential of tailor‐made supramolecular architectures in converting organic molecular crystals into versatile building blocks for advanced micro‐/nanophotonics and information encryption.

Thermoresponsive crystals linking molecular motion to macroscopic functions pose challenges in smart material integration. This work reports a new thermoresponsive organic crystal, 4‐((4‐(dimethylamino)phenyl)diazenyl)benzonitrile (Y28) exhibiting reversible thermally induced macroscopic expansion coupled with a sharp thermochromic switch. Through variable‐temperature single‐crystal X‐ray diffraction, spectroscopy, and response behavior analysis, it was found that the crystal underwent continuous elongation upon heating and that a color change from red to orange occurred at a specific temperature, which process is fully reversible. Structural analysis indicates that the slight, reversible adjustment of the twist angle and interlayer spacing is manifested optically as a decrease in the band gap and a color change from red to orange with increasing temperature. At 420 K, the symmetry center disappears, and the entire heating–cooling cycle shows an order–disorder phase transition. By combining variable‐temperature single‐crystal diffraction data with macroscopic in situ deformation measurements, a complete process from the atomic to the macroscopic scale is constructed. This qualitatively and quantitatively elucidates the physical nature of the anisotropic thermal expansion of the Y28 crystal, along with its excellent cyclic stability. Its multifunctional coupling response mechanism provides new ideas for designing next‐generation smart drive and optical sensing materials.

The development of organic crystals capable of direct light to mechanical work conversion is essential for advancing soft micro robotics. In this work, we report a novel class of triazene based photomechanical crystals that achieve significant light driven effects by triggering irreversible chemical and physical processes. Specifically, the DMF solvate of BNE follows a path of lattice phase transition induced by the escape of solvent molecules—a physical process that is irreversible yet exhibits a rapid response. In contrast, DNE crystals undergo intramolecular photodecomposition upon irradiation, and this irreversible chemical process generates a high single use mechanical energy output, enough to drive a significant displacement of microspheres. These two crystals can be conceptualized as prototypes for an inherently functionalized light driven micro gripper. DNE is suitable for scenarios requiring high energy single triggers, while BNE is characterized by its rapid response. This study not only provides two high performance light driven materials but also reveals an effective strategy for tailoring irreversible photomechanical responses through crystal engineering of molecular packing. Our findings offer a new paradigm for the rational design of task oriented intelligent soft micro actuators, catering to needs ranging from high force single use triggers to rapid response systems.

The stringent environmental regulations on uranium-containing wastewater have rendered traditional treatment methods largely inadequate, creating an urgent demand for high-performance and stable adsorbents. In this study, the modified UiO-66 with aminophosphonate groups (UiO-66-NH₂-P) was used to enhance its U(VI) removal capacity from water through the synergistic effect of multifunctional groups. U6NP retains a well-defined MOF framework after acid immersion(pH 1-2). Under optimal conditions, the maximum U(VI) adsorption capacity reaches 320.81 mg/g. The adsorption behavior conformed to the PSO kinetic equation and the Langmuir model, indicating a spontaneous endothermic process. Furthermore, density functional theory (DFT) calculations, combined with optimized fitting using a cluster model, were performed to analyze various coordination modes of UO₂²⁺ in this system. The results provide atomic-level insights for the rational design of high-performance and high-stability adsorbent materials.