A Water-Stable Metal–Organic Framework with a Double-Helical Structure for Fluorescent Sensing

Water
instability is a crucial limiting factor in the practical application
of most fluorescent metal–organic frameworks (MOFs). Here,
by introducing a fascinating double-helical structure generated through
dense stacking of organic ligands, a water-stable fluorescence MOF
has been synthesized, namely, [Cd2(tib)2(bda)2]·(solvent)n (1) [tib =1,3,5-tris­(1-imidazolyl) benzene; H2bda = 2,2′-biphenyl
dicarboxylic acid]. This helical structure helps to enhance the stability
of 1 against common organic solvents and water, even
acid/base aqueous solutions with a pH value ranging from 3 to 11.
Furthermore, this material can be a potential fluorescent sensor for
ketones.