Reversible luminescence tuning behavior in a thermal-stimuli-responsive anthracene-based coordination polymer

Abstract

A new coordination polymer {[Zn₂(ADDA)₂(DMF)(H₂O)₂]·(DMF)}_n (HPU-22) (H₂ADDA = 4,4′-(anthracene-9,10-diyl) dibenzoic acid) based on an anthracene ligand is designed to obtain a stimulus-responsive material. The fluorescence color of HPU-22 changes under thermal stimuli. Single-crystal structural analysis demonstrates a slight alteration in the distance between adjacent anthracene rings, resulting in the changes in the fluorescence color. The changed fluorescence can be restored by simply wetting the product. The stimulus-responsive mechanism has also been explored in detail by using other characterization procedures. Results demonstrate that the emission properties are dependent on the arrangement of anthracene. This work contributes to the understanding of the thermochromic luminescence mechanism and the development of thermochromic luminescence materials with excellent performance.