Chemically stable multilayered covalent organic nanosheets from covalent organic frameworks via mechanical delamination

TitleChemically stable multilayered covalent organic nanosheets from covalent organic frameworks via mechanical delamination
Publication TypeJournal Article
Year of Publication2013
AuthorsChandra, S, Kandambeth, S, Biswal, BP, Lukose, B, Kunjir, SM, Chaudhary, MV, BabaRao, R, Heine, T, Banerjee, R
JournalJournal of the American Chemical Society
Volume135
Issue47
Pagination17853-17861
Date PublishedNOV
ISSN0002-7863
Abstract

A series of five thermally and chemically stable functionalized covalent organic frameworks (COFs), namely, TpPa-NO2, TpPa-F-4, TpBD-(NO2)(2), TpBD-Me-2, and TpBD-(OMe)(2) were synthesized by employing the solvothermal aldehyde-amine Schiff base condensation reaction. In order to complete the series, previously reported TpPa-1, TpPa-2, and TpBD have also been synthesized, and altogether, eight COFs were fully characterized through powder X-ray diffraction (PXRD), Fourier transform IR (FT-IR) spectroscopy, C-13 solid-state NMR spectroscopy, and thermogravimetric analysis. These COFs are crystalline, permanently porous, and stable in boiling water, acid (9 N HCl), and base (3 N NaOH). The. synthesized COFs (all eight) were successfully delaminated using a simple, safe, and environmentally friendly mechanical grinding route to transform into covalent organic nanosheets (CONs) and were well characterized via transmission electron microscopy and atomic force microscopy. Further PXRD and FT-IR analyses confirm that these CONs retain their structural integrity throughout the delamination process and also remain stable in aqueous, acidic, and basic media like the parent COFs. These exfoliated CONs have graphene-like layered morphology (delaminated layers), unlike the COFs from which they were synthesized.

DOI10.1021/ja408121p
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

11.444

Divison category: 
Central NMR Facility
Physical and Materials Chemistry