Luminescent zinc metal-organic framework (ZIF-90) for sensing metal ions, anions and small molecules

We synthesize a zinc zeolite-type metal-organic framework, the zeolitic imidazolate framework (ZIF-90), which exhibits an intense blue luminescence excited under visible light. Luminescent studies indicate that ZIF-90 could be an efficient multifunctional fluorescence material for high sensitivity metal ions, anions and organic small molecules, especially for Cd2+, Cu2+, CrO42- and acetone. The luminescence intensity of ZIF-90 increases with the concentration of Cd2+ and decreases proportionally with the concentration of Cu2+, while the same quenched experimental phenomena appear in the sensing of CrO42-. With the increase of the amount of acetone, the luminescence intensity decreases gradually in the emulsions of ZIF-90. The mechanism of the sensing properties is studied in detail as well. This study shows that ZIF-90 could be a useful luminescent sensor for metal ions, anions and organic small molecules.