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Ultralight covalent organic framework/graphene aerogels with hierarchical porosity.

ABSTRACT: The fabrication of macroscopic objects from covalent organic frameworks (COFs) is challenging but of great significance to fully exploit their chemical functionality and porosity. Herein, COF/reduced graphene oxide (rGO) aerogels synthesized by a hydrothermal approach are presented. The COFs grow in situ along the surface of the 2D graphene sheets, which are stacked in a 3D fashion, forming an ultralight aerogel with a hierarchical porous structure after freeze-drying, which can be compressed and expanded several times without breaking. The COF/rGO aerogels show excellent absorption capacity (uptake of >200 g organic solvent/g aerogel), which can be used for removal of various organic liquids from water. Moreover, as active material of supercapacitor devices, the aerogel delivers a high capacitance of 269 F g^-1 at 0.5 A g^-1 and cycling stability over 5000 cycles.

SUBMITTER: Li C

PROVIDER: S-EPMC7501297 | biostudies-literature |

REPOSITORIES: biostudies-literature

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