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In this work, we integrated the concept of aggregation-induced emission (AIE) with the specific supramolecular recognition between K+ ions and crown ether moieties to develop more effective fluorometric K+ probes. We synthesized a novel crown ether-functionalized tetraphenylethene (TPE) derivative, TPE-(B15C5)4, via the thiol-ene click reaction of thiol-derivatized TPE, TPE-(SH)4, with maleimide-functionalized benzo-15-crown-5 (B15C5). In TPE-(B15C5)4, the TPE core and four outer B15C5 moieties serve as the AIE-active motif and supramolecular K+-recognizing functionalities, respectively. TPE- (B15C5)4 molecularly dissolves in THF with negligible fluorescence emission. As we have envisaged, upon K+ addition, TPE-(B15C5)4 can be effectively induced to aggregate due to K+-mediated cross-linking via the formation of K+/B15C5 (1/2 molar ratio) molecular recognition complex in a sandwiched manner …