Three multifunctional two-dimensional coordination polymers based on 1-(3-carboxybenzyl)-4,4′-bipyridinium ligand

Abstract

By utilizing the carboxybenzyl viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium chloride (HBcbpy·Cl), 1,3,5-benzenetricarboxylic acid (H3BTC) and varying different metal ions, three new coordination polymers [Cd(Bcbpy)(HBTC)(H2O)·2H2O]n (1), [Zn(Bcbpy)(HBTC)(H2O)·2H2O]n (2) and [Co2(Bcbpy)2(HBTC)2(H2O)2·4H2O]n (3) have been synthesized and structurally characterized. Compounds 1 and 2 have identical two-dimensional (2D) coordination layered structure, while compound 3 features 2D+2D→2D structure. It is interesting that compounds 1 and 2 exhibit electron transfer photochromism, while compound 3 displays hydrochromism through dehydration. At the same time, considering the high stability and fast photo-response, the photo-modulated fluorescence and the inkless erasable printing capability are investigated.