A Water-Stable Dual-Channel Luminescence Sensor for UO22+ Ions Based on an Anionic Terbium(III) Metal-Organic Framework.

A stable 3D TbIII -based metal-organic framework [Tb(BPDC)2 ]⋅(CH3 )2 NH2 (DUT-101) was synthesized, and it is the first efficient dual-channel luminescence sensor for aqueous UO22+ ions. DUT-101 contains an anionic three-dimensional framework and protonated dimethylamine molecules embedded within the channels. The intense green emission of DUT-101 could be highly selectively and sensitively quenched by UO22+ ions even in the presence of other competing metal ions. A possible sensing mechanism was proposed based on both suppression of luminescence resonance energy transfer and enhancement of intermolecular electron transfer. Furthermore, visual green fluorescent test papers based on DUT-101 were fabricated and could be used to discriminate UO22+ ions among various metal ions.