Full-Color Emissive D-D-A Carbazole Luminophores: Red to Near-Infrared Mechanofluorochromism, Aggregation-Induced Near-Infrared Emission, and Photodynamic Therapy Application.

Abstract

The preparation of multi-functionalized luminophores with full-color emission based on an identical core skeleton is a significative but challenging research topic. In this work, eight donor-donor-acceptor (D-D-A) type luminogens based on a central carbazole core bearing a hydrocarbon chain of six carbon atoms are designed by using different kinds of donor and acceptor units on the left and on the right and synthesized in good yields. These D-D-A carbazole derivatives display deep-blue, sky-blue, blue-green, green, yellow-green, yellow, orange and red fluorescence in the solid state, respectively, achieving full-color emission covering the whole visible light range under UV light illumination. Notably, dicyano-functionalized triphenylamine-containing carbazole derivative exhibits rare aggregation-induced near-infrared emission and red to near-infrared mechanofluorochromism with high contrast beyond 100 nm. Furthermore, red emissive luminogen can serve as a potential candidate for cell imaging and photodynamic therapy (PDT). The present work not only provides reference for the construction of full-color emissive systems but also opens a new avenue to the preparation of multi-functionalized luminophores capable of simultaneously applying in near-Infrared mechanical-force sensors and PDT fields.