Tetrazine quenchers were easily converted to pyridazine moieties by BCN-OH addition, and the aggregate emission of the obtained AIE-Pz was next investigated. Similar to AIE-Tz, AIE-Pz forms aggregates upon increasing water fraction. Because the tetrazine quencher is removed, AIE-Pz exhibits stronger emission both in dilute solutions and aggregates (Table , Supporting Information). Most importantly, AIE-Pzs demonstrates enhanced emission upon aggregation, unlike AIE-Tzs (Figure ). Specifically, TPE-Pz and MBTPA-Pz display the most typical AIE properties (Figure ), with significantly increased emission upon water addition. In contrast, TPA-Pz and MTPA-Pz exhibit twisted-intramolecular charge transfer (TICT) type AIEgen-like behavior: upon water addition, increased polarity causes charge separation in the excited state, initially quenching the emission. However, as the water fraction further increases, the emission is turned on again, induced by aggregate formation (Figure ). The PR-Pz negative control suffers from the ACQ effect and quenches its emission upon aggregation as expected (Figure ). In short, we achieved an emission enhancement system in AIE-Pzs aggregates.