Improved Durability and Activity of FeVO₄ toward Photocatalytic Benzene Hydroxylation by Atomic Layer Deposited Al₂O₃

Abstract

Selective hydroxylation of benzene to phenol over a visible light driven photocatalyst is a sustainable approach for the green synthesis of phenol. Iron vanadate (FeVO4) nanorods with an intrinsic photo‐Fenton catalytic behavior toward H2O2 activation is a promising candidate photocatalyst for the benzene hydroxylation reaction; however, its photocatalytic performance was greatly limited by the serious leaching of metals during the hydroxylation process. Herein, it has been demonstrated that this issue can be well addressed by the conformably coating of FeVO4 nanorods with an atomically‐precise thickness controlled dense Al2O3 layer (FeVO4@Al2O3) through the atomic layer deposition (ALD) technology. The Al2O3 nanolayer can well protect the FeVO4 nanorods from directly contacting with the reaction solution, thus effectively suppressing the leaching of metals during the photocatalytic hydroxylation process. In addition, the Al2O3 coating on FeVO4 also facilitates the kinetic control of heterogeneous benzene hydroxylation reaction over the catalyst surface, such as the benzene adsorption behavior and the photo‐Fenton activation of H2O2. As a result, FeVO4@Al2O3 exhibited an enhanced photocatalytic performance with a good durability in the long‐term production of phenol.