Ultralong Room-Temperature Phosphorescence from Organic-Inorganic Hybrid Perovskitoid Based on Metal-Organic Complex Component

Organic-inorganic hybrid perovskite or perovskitoid phosphorescent materials have aroused extensive research interests due to their applications in organic light emitting diodes, anti-counterfeiting, display, and other fields. Herein, a new strategy is proposed, employing metal-organic complex (MOC) cations as the organic components, which can increase the spin-orbit coupling (SOC) and intersystem crossing (ISC) efficiencies of the organic units, and hybrid with inorganic parts to form a novel type MOC-inorganic composed perovskitoid. In detail, a lead-free MOC-inorganic perovskitoid material, named P-Cl, is synthesized by self-assembly of preassembled MOC from metallized crown ethers with inorganic cadmium halide component. In the solid state, the assembled perovskitoid exhibits a tunable fluorescence color from blue to green, during which a cold white light emission is achieved. Interestingly, after removal of the radiation source, the perovskitoid still emits a bright and color-tunable long persistent luminescence (LPL) from cyan to green. Single-crystal X-ray diffraction analysis and theoretical calculations reveal that the bright LPL of P-Cl arises from the improvement of the metal-organic part to increase the SOC and the interlocking of metal halogenated layers to inhibit the nonradiative transition. The proposed strategy not only broadens the range of organic-inorganic perovskitoid hybrid materials but also facilitates the design of multifunctional LPL materials.