摘要
Ultra-long room temperature phosphorescence(URTP) has been increasingly recognized in pure organic luminophor in recent years. Through a simpler molecular design and charge separation-recombination pathway, organic luminophor can achieve even better URTP properties. In this work, we achieved URTP in a system of host-guest doped benzophenone derivatives whose phosphorescence is visible to the naked eye. The differences in the wavelength lifetimes of luminescent emission correspond to different photophysical mechanisms. Through a combination of theoretical calculations and experiments, the host acts as a powerful substrate that restricts the motion of the guest and inhibits the non-radiative transitions of the guest, accompanied by a charge transfer separation-recombination process between the host and the guest, resulting in an URTP phenomenon. Transient absorption results demonstrate the existence of a charge-separated state. The design strategy via charge separation is generic and easy to implement,providing a direction for the future design of doped URTP.
基金
supported by the National Natural Science Foundation of China (Nos. 21873068, 21573229 and 21422309)
the financial support from Double FirstRate and Peiyang Scholar Projects (Tianjin University)
the Open Research Funds of State Key Laboratory of Bioelectronics (Southeast University)
the Frontier Science Project of the Knowledge Innovation Program of Chinese Academy of Sciences (CAS)。