Highly Emissive Covalent Organic Frameworks.
Highly luminescent covalent organic frameworks (COFs) are rarely achieved because of the aggregation-caused quenching (ACQ) of π-π stacked layers. Here, we report a general strategy to design highly emissive COFs by introducing an aggregation-induced emission (AIE) mechanism. The integration of AIE-active units into the polygon vertices yields crystalline porous COFs with periodic π-stacked columnar AIE arrays. These columnar AIE π-arrays dominate the luminescence of the COFs, achieve exceptional quantum yield via a synergistic structural locking effect of intralayer covalent bonding and interlayer noncovalent π-π interactions and serve as a highly sensitive sensor to report ammonia down to sub ppm level. Our strategy breaks through the ACQ-based mechanistic limitations of COFs and opens a way to explore highly emissive COF materials.
Field of Energy and Environment, School of Materials Science, Japan Advanced Institute of Science and Technology , 1-1 Asahidai, Nomi 923-1292, Japan.
Sasanka
S
Dalapati
Department of Structural Molecular Science, School of Physical Science, SOKENDAI , Hayama, Kanagawa 240-0193, Japan.
Enquan
E
Jin
Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig , Linnéstrasse 2, 04103 Leipzig, Germany.
Matthew
M
Addicoat
Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig , Linnéstrasse 2, 04103 Leipzig, Germany.
Thomas
T
Heine
Field of Energy and Environment, School of Materials Science, Japan Advanced Institute of Science and Technology , 1-1 Asahidai, Nomi 923-1292, Japan.
Donglin
D
Jiang