Synthesis, characterization and explosive detection of photoluminescent compounds with intramolecular charge-transfer characteristic

Synthesis, characterization and explosive detection of compounds based on 1,4(benzo-{2,1′-3})-thiadiazole, carbazole, and tetraphenylethene derivatives with intramolecular charge-transfer characteristic were illustrated in detail. The photoluminescent variations of compounds in different solvents were studied, and emission light with different wavelength ranging from yellow, green to blue can be easily obtained by just changing the solvent without tedious synthetic modification. Furthermore, the titration experiments were used to detect explosive compound of picric acid, and then calculate the detection limit of the explosive by plotting curves of two compounds with aggregation–induced emission properties in tetrahydrofuran and tetrahydrofuran/water mixture solution of 90% water. The Stern–Volmer plots of carbazole and tetraphenylethene substituted 1,4(benzo-{2,1′-3})-thiadiazole in tetrahydrofuran and tetrahydrofuran/water mixture are linear in some concentration range and give quenching constants of 1.8 × 107 M−1 and 10.7 × 107 M−1, respectively, and the corresponding detect ion limits as low as 0.54 μg/mL and 0.13 μg/mL were realized. The detect ion performance of carbazole and tetraphenylethene substituted 1,4(benzo-{2,1′-3})-thiadiazole is much better than that of tetraphenylethene substituted 1,4(benzo-{2,1′-3})-thiadiazole, which can be attributed to the relatively higher dipole moment of the corresponding compound.