Three-primary-color molecular cocrystals showing white-light luminescence, tunable optical waveguide and ultrahigh polarized emission

Three-primary-color luminescent materials are highly desirable to construct white-light emitting resource, multi-color optical displays, and tunable photonic applications. However, the efficient strategy to establish the three-primary-color systems with unique photofunctionalities is still rather limited, particularly for molecular materials. Herein, we developed a molecular cocrystal route to obtain three-primary-color emissive materials by tuning different donor-acceptor units based on the same chromophore (4,4′-bis(2,5-dimethylstyryl)biphenyl, Bdb). The warm and cold white-light together with multi-color emission in most of visible region can be highly adjusted by rationally tuning different mixture components of three-primary-color cocrystals through an energy transfer mechanism. Furthermore, the blue/green/red emitters endow Bdb molecular cocrystals novel color-tunable photonic properties (such as one-dimensional (1D)/2D optical waveguide, polarized fluorescence, up-conversion luminescence, and amplified spontaneous emission), benefitting from their well-defined micro/nanostructures and high crystallinity. Particularly, the high luminescence quantum yield (82.49%) and polarized anisotropy (0.723) outperform most of state-of-the-art molecular crystalline materials. Therefore, this work supplies an effective way to fabricate new types of three-primary-color phosphors through luminescent cocrystals, which have promising applications in the fields of full-color displays, white-light irradiation, low-dimensional optical polarization, and micro/nanophotonics.[Figure not available: see fulltext.].