Turn-on fluorescence in a stable Cd(II) metal-organic framework for highly sensitive detection of Cr3+ in water

An extremely stable pillar-layered metal-organic framework (MOF), [Cd-4(NDC)(3)(4-Hptz)(2)(H2O)(2)]center dot H2O (1), has been successfully designed and synthesized (4-Hptz = 5-(4-pyridyl)-tetrazolate, NDC = 1,4-Naphthalenedicarboxylic acid). Compound 1 can detect Cr3+ in water by fluorescence enhancement, which is the first known case of MOF. This is of great significance for our study on new fluorescent probes.