Sensitive detection of nitroaromatic explosives such as picric acid is critical. Among various known methods, materials exhibiting aggregation-induced emission (AIE) have emerged as fascinating candidates for sensing multiple analytes. We report, synthesis of novel AIE active cyanostilbenes bearing benzimidazole moiety at one end and a phenyl group bearing electron-donating amino groups at the other terminal. The compounds show excellent AIE emission in aqueous media, and the addition of picric acid results in emission quenching accompanied by sharp color demarcation. Compounds also show strong selectivity for picric acid compared to other nitroaromatic and phenolic substrates with a ppm level of detection. The mechanistic details of the sensing mechanism were elucidated using ¹H NMR measurements that reveal the H-bonding interaction of picric acid with the fluorophores. The results demonstrate that these novel benzimidazole-fluorophores could be potential candidates for the selective and sensitive detection of picric acid.

敏感检测硝基苦味炸药（例如苦味酸）至关重要。在各种已知方法中，具有聚集诱导发射（AIE）的材料已成为用于感测多种分析物的引人入胜的候选材料。我们报告，合成的新型AIE活性氰基苯甲酸酯在一端带有苯并咪唑部分，而在另一端带有带有给电子氨基的苯基。这些化合物在水性介质中显示出出色的AIE发射，而苦味酸的添加会导致发射猝灭并伴有清晰的颜色分界。与其他硝基芳香族和酚类底物相比，该化合物对苦味酸的选择性也很强，检测水平为ppm。使用¹阐明了感应机制的机械细节。1 H NMR测量揭示了苦味酸与荧光团的氢键相互作用。结果表明，这些新颖的苯并咪唑荧光团可能是选择性和灵敏检测苦味酸的潜在候选者。