How Structure-Directing Cations Tune the Fluorescence of Metal–Organic Frameworks

A series of metal-organic frameworks (MOFs), {Zn-BTC}­{cations}, which contain anionic Zn-BTC coordination polymers, is reported here. It was observed that cations with different hydrogen-bond forming abilities could significantly affect the coordination of Zn-BTC structures in the frameworks. The 13 Zn-BTC MOFs reported herein showed solid-state fluorescent emission in the visible spectrum, and the fluorescence of the frameworks was tunable by adjusting the interactions of the cations with the anionic Zn-BTC structure in the MOFs.