Perfluoroalkyl-modified covalent organic frameworks for continuous photocatalytic hydrogen peroxide synthesis and extraction in a biphasic fluid system.

HO photosynthesis represents an appealing approach for sustainable and decentralized HO production. Unfortunately, current reactions are mostly carried out in laboratory-scale single-phase batch reactors, which have a limited HO production rate (<100 μmol h) and cannot operate in an uninterrupted manner. Herein, we propose continuous HO photosynthesis and extraction in a biphasic fluid system. A superhydrophobic covalent organic framework photocatalyst with perfluoroalkyl functionalization is rationally designed and prepared via the Schiff-base reaction. When applied in a home-built biphasic fluid photo-reactor, the superhydrophobicity of our photocatalyst allows its selective dispersion in the oil phase, while formed HO is spontaneously extracted to the water phase. Through optimizing reaction parameters, we achieve continuous HO photosynthesis and extraction with an unprecedented production rate of up to 968 μmol h and tunable HO concentrations from 2.2 to 38.1 mM. As-obtained HO solution could satisfactorily meet the general demands of household disinfection and wastewater treatments.