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A Nanographene-Based Two-Dimensional Covalent Organic Framework as a Stable and Efficient Photocatalyst.

ABSTRACT: Synthesis of covalent organic frameworks (COFs) with desirable organic units furnishes advanced materials with unique functionalities. As an emerging class of two-dimensional (2D) COFs, sp² -carbon-conjugated COFs provide a facile platform to build highly stable and crystalline porous polymers. Herein, a 2D olefin-linked COF was prepared by employing nanographene, namely, dibenzo[hi,st]ovalene (DBOV), as a building block. The DBOV-COF exhibits unique ABC-stacked lattices, enhanced stability, and charge-carrier mobility of ≈0.6 cm² V^-1 s^-1 inferred from ultrafast terahertz photoconductivity measurements. The ABC-stacking structure was revealed by the high-resolution transmission electron microscopy and powder X-ray diffraction. DBOV-COF demonstrated remarkable photocatalytic activity in hydroxylation, which was attributed to the exposure of narrow-energy-gap DBOV cores in the COF pores, in conjunction with efficient charge transport following light absorption.

SUBMITTER: Jin E

PROVIDER: S-EPMC9299764 | biostudies-literature |

REPOSITORIES: biostudies-literature

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