Construction of a zeolite A-type multivariate metal-organic framework for selective sensing of Fe3+ and Cr2O72-

Construction of zeolite-type frameworks is of broad interest and mainly achieved by using imidazolate linkers. Incorporation of multiple linkers/functionalities into these unique types of frameworks would potentially expand their application scope. Herein, a three-dimensional (3D) metal-organic framework, BUT-27, with a unique zeolite A structure (LTA topology) was synthesized by linker exchange via single-crystal-to-single-crystal transformation. Addition of isophthalic acid linker to the two-dimensional double layered BUT-25 changed the whole framework to a 3D structure, BUT-27, containing three kinds of linkers. The strong fluorescence and presence of free O and N atoms in the framework make BUT-27 a good luminescent sensor for the detection of Fe3+ and Cr2O72- ions with high selectivity and sensitivity, i.e. K-sv = 1.1 x 10(4) and 5.9 x 10(4), and LOD (limit of detection) of 0.19 and 0.26 mu M, respectively. These values are lower than the minimum values specified by US-EPA (United States Environmental Protection Agency) indicating its high potential for practical applications.

Automated summary

A novel three-dimensional metal-organic framework, BUT-27, with a unique zeolite A structure was synthesized by incorporating new linkers into a two-dimensional framework, demonstrating high potential for practical applications as a luminescent sensor.