Host-guest doping induced excited state energy transfer for efficient room temperature phosphorescence emission

Abstract

The 1,8-naphthalimide derivatives as the guest and the benzophenone (BP) analogues bis(4-chlorophenyl)methanone (BP2C) and bis(4-fluorophenyl)methanone (BP2F) benzophenone derivatives as the host, we constructed a series of novel doping systems with fluorescence and room temperature phosphorescence (RTP) dual emission. The steady-state spectroscopy, ultrafast spectroscopy techniques, and theoretical calculations indicate that Förster resonance energy transfer (FRET) between singlet states between host and guest components enables energy redistribution in doped systems. At the same time, the Dexter energy transfer (DET) between the triplet states realizes the obvious absorption of the excited triplet state of the guest, resulting in the long-lived room temperature phosphorescence of the doped system. Doping materials have unlimited potential for information storage and anti-counterfeiting by exploiting the properties of photo activation.