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Covalent Organic Framework (COF-1) under High Pressure.

ABSTRACT: COF-1 has a structure with rigid 2D layers composed of benzene and B3 O3 rings and weak van der Waals bonding between the layers. The as-synthesized COF-1 structure contains pores occupied by solvent molecules. A high surface area empty-pore structure is obtained after vacuum annealing. High-pressure XRD and Raman experiments with mesitylene-filled (COF-1-M) and empty-pore COF-1 demonstrate partial amorphization and collapse of the framework structure above 12-15?GPa. The ambient pressure structure of COF-1-M can be reversibly recovered after compression up to 10-15?GPa. Remarkable stability of highly porous COF-1 structure at pressures at least up to 10?GPa is found even for the empty-pore structure. The bulk modulus of the COF-1 structure (11.2(5)?GPa) and linear incompressibilities (k[100] =111(5)?GPa, k[001] =15.0(5)?GPa) were evaluated from the analysis of XRD data and cross-checked against first-principles calculations.

SUBMITTER: Sun J

PROVIDER: S-EPMC7065212 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Covalent Organic Framework (COF-1) under High Pressure.

Sun Jinhua J Iakunkov Artem A Baburin Igor A IA Joseph Boby B Palermo Vincenzo V Talyzin Alexandr V AV

Angewandte Chemie (International ed. in English) 20191202 3

COF-1 has a structure with rigid 2D layers composed of benzene and B3 O3 rings and weak van der Waals bonding between the layers. The as-synthesized COF-1 structure contains pores occupied by solvent molecules. A high surface area empty-pore structure is obtained after vacuum annealing. High-pressure XRD and Raman experiments with mesitylene-filled (COF-1-M) and empty-pore COF-1 demonstrate partial amorphization and collapse of the framework structure above 12-15 GPa. The a ...[more]

PMID: 31553513

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