A 3D Phosphorescent Supramolecular Organic Framework in Aqueous Solution

Supramolecular organic framework (SOF) has recently garnered significant research interest in the field of luminescent materials. However, SOF with room-temperature phosphorescence emission in solution is very rare due to the quenching of dissolved oxygen and free molecular motions, which would lead to nonradiative deactivation of triplet exciton in liquid state. In this work, a 3D cationic phosphorescent SOF is synthesized through host-guest interaction between CB[8] and a tetrahedral monomer TBBP, which can rapidly adsorb anionic guests in solution. When anionic dyes are introduced, triplet to singlet Forster resonance energy transfer (TS-FRET) in solution can be achieved, and delayed fluorescence with large Stokes shift can be realized. Additionally, when anionic drugs are introduced, the phosphorescence of TBBP-CB[8] can be quenched due to charge transfer, enabling the detection of drugs through phosphorescence signals. Taking advantage of the fast adsorption property of 3D SOF, an INHIBIT logic gate with three inputs and two outputs is constructed. These findings provide a novel method to prepare phosphorescent functional materials and a new pathway to construct TS-FRET system in solution. A 3D phosphorescent cationic supramolecular organic framework is constructed via the host-guest interaction between TBBP and CB[8], which could rapidly adsorb anionic guests like drugs and dyes in solution, accompanied by significant changes in optical properties. These findings provide a new pathway to construct delayed luminescence system through TS-FRET and drug detection system in aqueous solution. image