Nearly Unity Quantum Yield Persistent Room‐Temperature Phosphorescence from Heavy Atom‐Free Rigid Inorganic/Organic Hybrid Frameworks. (25th July 2022) - Zheng, Xin
Abstract: Synergism between covalent and non‐covalent bonds is employed to fix an organic phosphor guest in a rigid inorganic framework, simulating the stiffening effect seen in the glassy state and realizing efficient and ultralong room‐temperature phosphorescence (RTP). Twelve heavy‐atom‐free composites have been obtained through introducing arylboric or arylcarboxylic acid derivatives into the inorganic boric acid matrix by solid‐phase synthesis. Owing to the stiffening effect of multiple bonds, all the composites show highly efficient and persistent RTP of guest molecules with a quantum yield ranging from 39.8 % to ca. 100 % and a lifetime up to 8.74 s, which results in a 55 s afterglow visible to the naked eye after exposure to a portable UV lamp. Interestingly, it is found that the substitution position and quantity of carboxyl in the guest have a great influence on the phosphorescent properties, and that the heavy‐atom effect is invalid in such host–guest hybrid systems. The 100 g grade composite is easily prepared because of the solvent‐free, green, and simple synthesis method. These results provide an important way for the development of RTP materials with ultrahigh quantum yield and ultralong lifetime, as well as their practical applications in the fields of anti‐counterfeiting and information storage, among others. Abstract : A series of heavy atom‐free inorganic/organic hybrid composites are prepared by a simple and green solid‐phase method. Through the synergism of covalent and non‐covalent bonds, the organic guest phosphors can be completely fixed in the inorganic matrix, just like in the low‐temperature glass state, thus exhibiting highly efficient and persistent room‐temperature phosphorescence with quantum yields up to 100 % and average lifetimes up to 8.74 s.