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Chemical structures bearing a combination of aggregation-induced emission enhancement (AIEE) and intramolecular charge transfer (ICT) properties attracted the attention of many researchers. Recently, there is an increasing demand to pose tunable AIEE and ICT fluorophores that could present their conformation changes-related emission colors by adjusting the medium polarity. In this study, we designed and synthesized a series of 4-alkoxyphenyl-substituted 1,8-naphthalic anhydride derivatives NAxC using the Suzuki coupling reaction to construct donor–acceptor (D-A)-type fluorophores with alkoxyl substituents of varying carbon chain lengths (x = 1, 2, 4, 6, 12 in NAxC). To explain the observation that molecules with longer carbon chains revealed unusual fluorescence enhancement in water, we study the optical properties and evaluate their locally excited (LE) and ICT states by solvent effects combined with Lippert–Mataga plots. Then, we explored the self-assembly abilities of these molecules in water-organic (W/O) mixed solutions and observed the morphology of its nanostructure using a fluorescence microscope and SEM. The results show that NAxC, x = 4, 6, 12 show different degrees of self-assembly behaviors and corresponding aggregation-induced emission enhancement (AIEE) progresses. At the same time, different nanostructures and corresponding spectral changes can be obtained by adjusting the water ratio in the mixed solution. That is, NAxC compounds present different transitions between LE, ICT and AIEE based on the polarity, water ratio and time changes. We designed NAxC as the structure–activity relationship (SAR) of the surfactant to demonstrate that AIEE comes from the formation of micelle-like nanoaggregates, which causes a restriction of the transfer from the LE state to the ICT state, and micelle formation results in a blue-shift in emission and enhances the intensity in the aggregate state. Among them, NA12C is most likely to form micelles and the most obvious fluorescence enhancement, which will switch over time due to the nano-aggregation transition.

Flame-retardant chemicals are frequently used within consumer products and can even be employed as a treatment on the surface of different types of materials (e.g., wood, steel, and textiles) to prevent fire or limit the rapid spread of flames. Functionalized graphene oxide (FGO) nanosheets are a promising construction coating nanomaterial that can be blended with sodium metasilicate and gypsum to reduce the flammability of construction buildings. In this work, we designed and fabricated novel and halogen-free FGO sheets using the modified Hummers method; and subsequently functionalized them by pentaerythritol through a chemical impregnation process before dispersing them within the construction coating. Scanning electron microscopic images confirm that the FGO-filled coating was uniformly dispersed on the surface of wooden substrates. We identified that the FGO content is a critical factor affecting the fire retardancy. Thermogravimetric analysis of the FGO coating revealed that higher char residue can be obtained at 700 °C. Based on the differential scanning calorimetry, the exothermic peak contained a temperature delay in the presence of FGO sheets, primarily due to the formation of a thermal barrier. Such a significant improvement in the flame retardancy confirms that the FGO nanosheets are superior nanomaterials to be employed as a flame-retardant construction coating nanomaterial for improving thermal management within buildings.

Tricyclic acridone derivatives have been extensively developed as antimicrobial, antimalarial, and antitumor drugs due to their broad spectrum of drug design and biological activity. In this study, we developed a surfactant-like acridone scaffold that contained two vinylpyridines and a dodecyl pyridine chain. The acridone scaffold decorated the dodecyl pyridine chain by N-bromosuccinimide reagent. The surfactant-like core scaffold incorporated with 4-vinylpyridines at the 2- and 7-positions via a Heck coupling reaction. Subsequently, the acridone derivatives were methylated onto these pyridine groups. Here we developed two similar acridone derivatives, MedAcd12C and MedAcd12P. The MedAcd12C incorporated two pyridine groups, and MedAcd12P incorporated three pyridine groups. MedAcd12C and MedAcd12P have two identical vinylpyridines and the different anchor tails at the N10 position. Their physicochemical properties, cell compatibility, and photoluminescence were demonstrated. Although both compounds have no fluorescence emission in water solution, MedAcd12P and MedAcd12C significantly appeared with orange light emission in the cellular imaging. We suggested that the surfactant-like scaffold promoted the drugs’ self-assembly and caused the aggregation-induced emission (AIE) after cellular uptake. This innovative design endowed acridone derivatives with an AIE and traceability for cell imaging.