Anthracene-Resorcinol Derived Covalent Organic Framework as Flexible White Light Emitter
摘要:
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 pi-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.
hydrothermal procedure has been developed to produce azine-linked COFs by conducting condensation reactions of hydrazine with hydroxy-substituted 1,3,5-triformylbenzene in water. The synthesis of one representative COF was drastically promoted by water in comparison with the traditional solvothermal reactions in organic solvents. This synthesis has advantages of large-scale production, catalyst-free
[EN] COVALENT ORGANIC FRAMEWORK AND METHODS OF FABRICATION AND USES THEREOF<br/>[FR] ÉDIFICE ORGANIQUE COVALENT ET SES PROCÉDÉS DE PRÉPARATION ET UTILISATIONS ASSOCIÉES
申请人:NAT UNIV SINGAPORE
公开号:WO2020214095A1
公开(公告)日:2020-10-22
The present invention relates to, in general, methods of fabricating a covalent organic framework (COF) and the COF thereof. In particular, the method comprises forming an acylhydrazone bond with an optionally substituted 2-alkoxybenzohydrazidyl moiety. The resultant COF has an x-ray diffraction 2-theta peak at about 3˚ with a full width half maximum (FWHM) of about 0.2˚ to about 0.4˚.
作者:S. Hessam M. Mehr、Hannah Depmeier、Katsuya Fukuyama、Mahboobeh Maghami、Mark J. MacLachlan
DOI:10.1039/c6ob02727j
日期:——
We report a new method to formylate phenol derivatives using formamidine acetate and acetic anhydride. This general-purpose transformation is a significant improvement over many other methods and does not require high temperatures or the addition of strong acid or base. Mono-, di-, and tri-formylated product can be obtained, depending on the substrate and conditions used.
Acridine‐Functionalized Covalent Organic Frameworks (COFs) as Photocatalysts for Metallaphotocatalytic C−N Cross‐Coupling
作者:Michael Traxler、Sebastian Gisbertz、Pradip Pachfule、Johannes Schmidt、Jérôme Roeser、Susanne Reischauer、Jabor Rabeah、Bartholomäus Pieber、Arne Thomas
DOI:10.1002/anie.202117738
日期:2022.5.16
A new family of porous crystalline COFs bearing acridine moieties was synthesized and applied as photocatalysts in metallaphotocatalyticC−N cross-coupling. Among these materials the fully β-ketoenamine-linked COF showed the highest catalytic activity and was shown to be recyclable and even catalyzed the cross-coupling efficiently under green light irradiation.
Programmable Photocatalytic Activity of Multicomponent Covalent Organic Frameworks Used as Metallaphotocatalysts
作者:Michael Traxler、Susanne Reischauer、Sarah Vogl、Jérôme Roeser、Jabor Rabeah、Christopher Penschke、Peter Saalfrank、Bartholomäus Pieber、Arne Thomas
DOI:10.1002/chem.202202967
日期:2023.1.18
Various multicomponent COFs bearing both a moiety for photosensitization and complexation of nickel catalysts were synthesized using reticulation with different 1,3,5-triformylbenzene nodes. This enabled the switching between persistent, charge-separated species or efficient charge-carrier mobility for different metallaphotocatalytic cross-coupling reactions based on the node unit. The frameworks showed