One-dimensional La(III) coordination polymer displaying multi-responsive luminescence activities towards Fe3+, acetone and benzothiozoles

Abstract Through reaction of La(NO3)3 with a flexible carboxylic acid ligand named 3,5-bis[(2-carboxyphenyl)oxy]benzoic acid (H3L) under solvothermal condition, the complex with the formula of [La(L)(DMF)2] (1) was obtained. One-dimensional chain of the complex was generated through the connection of binuclear units of La2(COO)4 across the flexible acid ligands. Luminescence results showed that different pollutants (Fe3+, acetone and benzothiophene organic compounds) could quench the luminescence of the blue emission of the complex in DMF with much low detection limit. Among several 2-substituted benzothiophene compounds, 2,2′-dithiobisbenzothiazole (DM) has a strongest binding constant of 10.8 ​× ​104 ​M−1 and lowest detection limit of 0.332 ​μM (0.110 ​ppm). All quenching effect was found within 15 ​s. The sensing mechanism was investigated through a series of experiments and theoretical calculation. Complex 1 could be employed as a multi-responsive chemsensor for detection of different pollutants with high sensitivity and fast response.