Three-dimension hierarchical heterostructure of CdWO4 microrods decorated with Bi2WO6 nanoplates for high-selectivity photocatalytic benzene hydroxylation to phenol

For the first time Bi2WO6/CdWO4 (BCW) hierarchical heterostructure of CdWO4 microrods decorated with uniform Bi2WO6 nanoplates was prepared. Using BCW as photocatalyst and O2 as oxidant, we achieved satisfactory catalytic activity (benzene conversion 7.3% and selectivity of phenol > 99%) in the hydroxylation of benzene to phenol at room temperature. It was found that the unique hierarchical heterostructure is beneficial for the absorption of visible light and the separation of photoinduced charge carriers. Moreover, we confirm the pivotal role of hydroxyl radicals and propose a plausible mechanism for the hydroxylation reaction.