F-doped Bi2WO6 with rich oxygen vacancies for boosting photo-oxidation/reduction activity

The erythrocyte-like F-doped Bi2WO6 (F-Bi2WO6) with rich oxygen vacancies was fabricated via a simple one-step hydrothermal method. With the help of various characterization techniques, it was determined that F− anions were doped into the Bi2WO6 lattice together with the generation of oxygen vacancies in the doping process. The oxygen vacancy as an electron acceptor in Bi2WO6 could tune band structure and trap the electrons easily to generate a new quick channel of electron transport, thus promoting the separation and transfer of e−-h+ pairs. The F-Bi2WO6 photocatalysts exhibited superior properties in photocatalytic activity, photocarrier separation and visible-light absorption compared with the pristine Bi2WO6. And the optimized F1.00-Bi2WO6 displayed a remarkable 1.6 and 2.5 times enhanced photocatalytic Cr(VI) reduction and MO degradation activities than the pristine Bi2WO6, respectively. Consequently, the enhanced photocatalytic mechanisms were elaborated for the Cr(VI) reduction and MO degradation under visible-light, respectively.