Luminescence tuning with excellent colour homogeneity and steadiness using fluorescent molecular liquids

Abstract

Solvent-free multicolour-emitting soft materials are promising candidates for burgeoning flexible light-emitting devices. Although significant effort has been devoted to the colour tunability of luminophores, the quality of the colour has remained inconspicuous. In the present study, we achieved a homogeneous and steady regulated luminescence colour through the chemical modification of fluorescent molecular liquids. An alkylated 2,6-dibromo-9,10-diphenylanthracene liquid was used as a case study, the fluorescence of which was tuned by either extending the length of the π-conjugation or incorporating an intramolecular charge transfer transition. The resulting liquids emitted different colours spanning from deep blue to green. Each colour exhibits an advantageous uniformity and steadiness over those of conventional colour-tuning systems, such as the blending of a luminescent liquid with other emissive solid dopants, demonstrating significant promise for the long-term consistency of the end-use luminescent performance.