Solvent Polarity Triggered Rapidly Reversible Quadruple‐Mode Luminescence Adjustment in 0D Hybrid Antimony Halides

Abstract Zero‐dimension (0D) organic‐inorganic hybrid metal halides are highly attractive as smart responsive luminescent materials, but the multiple‐mode luminescence switch is rarely achieved and intrinsic solvochromism mechanism is unclear. Herein, we report a yellowish‐green‐emitting (Me3BzN)3Sb2Cl9 (Me3BzN: trimethylbenzyl ammonium) single crystal, revealing quadruple/triple‐mode luminescence switch with rapid response time (<1 s) and excellent recyclability (≥ 100 cycles) when triggered by moderately‐polar and strongly‐polar solvents. Significantly, the intrinsic solvochromism mechanism is systematically proposed, of which the reversibly multiple‐mode luminescence tuning is closely related to solvent polarity, the moderate polarity can lead to luminescence redshift from 560 to 670 nm due to the increase of dipole moment for inorganic polyhedron. Besides, the small molecular solvent with strong polarity can insert into crystal and form “host‐guest” system, inducing single crystal‐single crystal phase transformation with structural disorder and Sb‐Sb distance variation. Owing to the unique multiple‐mode luminescence adjustment performance, (Me3BzN)3Sb2Cl9 displays potential candidate in solvent detection, safety monitoring and information encryption scenarios. These findings highlight the significance of solvent polarity and molecule volume on the dynamic luminescence adjustment and offer guidance for the development of new smart responsive 0D hybrid antimony halides in advanced optical switchable fields.