Control of Multicolor and White Emission by Triplet Energy Transfer.

A new strategy by manipulating the progress of triplet energy transfer (TET) is developed to realize adjustable multicolor and pure white emission. Donor phosphorescent molecules emits light when encapsulated into polyvinyl alcohol (PVA) through hydrogen bond interactions, and acceptor fluorescent molecules emits light when doped into PVA through cation-π interactions and hydrogen bond interactions. In addition, the triplet to singlet energy transfer process and mechanism are proved using the energy diagram and lifetime. The broadband emission color of the obtained composite film can be easily modulated by simply adjusting the amount and component of dyes, especially the white emission with CIE coordinates of (0.339, 0.337). This work provides a facile and versatile method for the development of multicolor and pure white-light-emitting diodes, which uses the interactions to light up luminescence properties, and can further aid in the wide development of applications for TET in various other fields.