Anthracene-Resorcinol Derived Covalent Organic Framework as Flexible White Light Emitter

• DOI: 10.1021/jacs.8b08312
• Publication Date: 2018-09-26T20:10:10Z
• Authors: Sattwick Haldar; Debanjan Chakraborty; Bibhisan Roy; Gangadhar Banappa...; Kushwaha Rinku; Dinesh Mullangi; Partha Hazra; Dinesh Kabra; Ramanathan Vaidhy...
• Keywords: DEVICES; CONSTRUCTION; DERIVATIVES; LUMINESCENT; HETEROJUNCTIONS; 535; 02 engineering and technology; CRYSTALLINE; NANOPARTICLES; DIODES; EMISSION; 0210 nano-technology; CONJUGATED POLYMERS

The ordered modular structure of a covalent organic framework (COF) facilitates the selective incorporation of electronically active segments that can be tuned to function cooperatively. This designability inspires developing COF-based single-source white light emitters, required in next-generation solid-state lighting. Here, we present a new anthracene-resorcinol-based COF exhibiting white light emission. The keto-enol tautomers present in the COF give rise to dual emission, which can be tuned by the O-donor and N-donor solvents. Importantly, when suspended in a solid polymer matrix, this dual emission is retained as both tautomers coexist. A mere 0.32 wt % loading of the COF in poly(methyl methacrylate) (PMMA) gives a solvent-free film with intense white light emission (CIE coordinates (0.35, 0.36)). From steady-state and time-resolved studies, the mechanism of the white light emission has been unambiguously assigned to fluorescence, with the blue emission originating from the π-stacked columns of anthracene, and the mixture of red and green from the keto-enol tautomerized resorcinol units. The study introduces the COF as a new class of readily processable, single-source white light emitter.