2,4,6-Trinitrophenol (TNP) has been widely used as a common explosive, but it pollutes the environment and the water source. The selective and sensitive detection of TNP in a water environment is of great importance. Herein, two facile and sensitive fluorescent sensing films (TCTSp-EP and OCTSp-EP) were constructed using tetrabazolyl- and octacarbazolyl-substituted spirobifluorene star-shaped molecules (TCTSp and OCTSp) by electrochemical polymerization. The TCTSp-EP and OCTSp-EP were found selective and sensitive towards the detection of TNP, with a limit of detection (LOD) value of 47.2 nM and 21.5 nM, respectively. The fluorescence detection of TNP was achieved through Förster resonance energy transfer (FRET) and photo-induced electron transfer (PET) as core TNP detection mechanisms. Compared with TCTSp-EP, the more carbazoles in the OCTSp-EP improved the electrical activity and increased the film thickness growth rate. The OCTSp-EP was more sensitive to TNP in water than TCTSp-EP. This was due to the hyperbranched structure of OCTSp-EP which had more exciton migration channels. Moreover, both of these films had excellent cycling performance and were successfully applied to detect TNP in real-water samples (deionized water, drinking water, and lake water).

2,4,6-三硝基苯酚(TNP)作为一种常见炸药被广泛使用,但它会污染环境和水源。水环境中TNP的选择性和灵敏检测具有重要意义。在此，使用四巴唑基和八咔唑基取代的螺二芴星形分子（TCTSp和OCTSp）通过电化学聚合构建了两种简便且灵敏的荧光传感膜（TCTSp-EP和OCTSp-EP）。TCTSp-EP 和 OCTSp-EP 对 TNP 的检测具有选择性和敏感性，检测限 (LOD) 值分别为 47.2 nM 和 21.5 nM。TNP的荧光检测是通过福斯特共振能量转移（FRET）和光诱导电子转移（PET）作为核心TNP检测机制实现的。与TCTSp-EP相比，OCTSp-EP中更多的咔唑提高了电活性并增加了膜厚度增长率。OCTSp-EP 对水中的 TNP 比 TCTSP-EP 更敏感。这是由于OCTSp-EP的超支化结构具有更多的激子迁移通道。此外，这两种薄膜都具有优异的循环性能，并成功应用于实际水样（去离子水、饮用水和湖水）中TNP的检测。