Unique functionalities of carbon shells coating on ZnFe2O4 for enhanced photocatalytic hydroxylation of benzene to phenol

Abstract

Hydroxylation of benzene to phenol over a photocatalyst is a green approach toward phenol production. ZnFe2O4 (ZFO) with an intrinsic peroxidase-like catalytic behavior toward H2O2 activation is an emerging photocatalyst for benzene hydroxylation reaction; however, its catalytic performance is greatly limited by the fast charge recombination, inevitable metal leaching and hydrophilic surface structure. Herein, the encapsulation of ZFO by carbons (ZFO@C) is an effective solution to address these issues. The carbons conformably coating on ZFO not only protect them from corrosion and metal leaching, but also enable the generation of a strong electronic contact between them to facilitate charge separation. In addition, the carbons also increase the surface affinity for benzene adsorption. As a result, ZFO@C exhibited a significant enhanced photocatalytic activity and durability for phenol synthesis. Furthermore, ZFO@C with carbon derived unique functionalities will have a broad application in photocatalytic green synthesis of fine chemicals.