Two superior luminescent zinc(II) coordination polymers sensors based on a bifunctional groups ligand: Detecting trace nitro explosive picric acid

摘要

Two luminescent zinc(If) coordination polymers {[Zn-3(PIDPE)(O)(chdc)(2.5)]}(n) (1) and {[Zn(PIDPE)(hdc)]}(n), (2) [4-(pyridyl)-4'-(imidazol-1-yl) diphenyl ether (PIDPE), Hexanedioic acid (H(2)hdc), 1,4-Cyclohexanedicarboxylic acid (H2chdc)] were prepared. Complex 1 reveals a 3D framework with infinitely 1D [ZnOZn(COO)](n) chain, complex 2 reveals [2 + 2] interpenetrated 3D framework. Fluorescence sensing experiments show that the complex 2 has higher selectivity and sensitivity for fluorescence sensing picric acid (PA) than complex 1, the K-sv is as high as 0.3 mu M, higher than most reported coordination polymers. Furthermore, complex 2 can be recovered and regenerated by simple washing. The possible detection mechanisms of complexes 1 and 2 as luminescent sensor have been discussed as well from photo-induced electron transfer (PET) and resonance energy transfer (RET) perspective.