21:T4a9,A water-stable and pH-independent sensor for qualitative and quantitative detection of nicotine in urine solution and living cell was successfully developed. This material, named MB@UiO-66-NH₂, can be synthesized by encapsulating methylene blue (MB) with a well-known metal-organic framework (MOF) UiO-66-NH₂ through a simple impregnation method. The fluorescence intensity of the system was significantly enhanced when a certain amount of nicotine was added. In the meanwhile, MB is reduced by reductive nicotine to form leucomethylene blue (LB). The proposed sensor displayed excellent selectivity and sensitivity toward nicotine with limit of detection (LOD) of 0.98 μM, which is comparable or even better than that of the electrochemistry detecting methods for nicotine. The obvious enhancement and blue shift of the emission arise from the photoinduced electron transfer (PET) from LB to the UiO-66-NH₂. The photophysical properties and the sensing applications of MB@UiO-66-NH₂ suggest that this composite can be acted as a sensitive, selective, recyclable, and fluorogenic sensor for nicotine determination in urine solution and living cell.22:T500,Thermally activated delayed fluorescence (TADF) emitters with a high horizontal orientation are highly essential for improving the external quantum efficiency (EQE) of organic light-emitting diodes; however, pivotal molecular design strategies to improve the horizontal orientation of solution-processable TADF emitters are still scarce and challenging. Herein, a phenyl bridge is adopted to connect the double TADF units, and generate a dimerized TADF dendrimer, D4CzBNPh-SF. Compared to its counterpart with a single TADF unit, the proof-of-the-concept molecule not only exhibits an improved horizontal dipole ratio (78 %) due to the π-delocalization-induced extended molecular conjugation, but also displays a faster reversed intersystem crossing rate constant (6.08×10⁶ s^-1) and a high photoluminescence quantum yield of 95 % in neat film. Consequently, the non-doped solution-processed device with D4CzBNPh-SF as the emitter achieves an ultra-high maximum EQE of 32.6 %, which remains at 26.6 % under a luminance of 1000 cd/m². Furthermore, when using D4CzBNPh-SF as a sensitizer, the TADF-sensitized fluorescence device exhibits a high maximum EQE of 30.7 % at a luminance of 575 cd/m² and a full width at half maximum of 36 nm.

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