Highly efficient photocatalytic oxidation of phenol over ordered mesoporous Bi2WO6

Ordered mesoporous Bi2WO6 (M-Bi2WO6) with nanocrystalline walls was fabricated for the first time by a silica-templated nanocasting method with bismuth nitrate and phosphotungstic acid as precursors. The as-prepared mesoporous Bi2WO6 sample exhibited a much higher photocatalytic activity than the conventional hydrothermally synthesized nanoscale Bi2WO6 (HR-Bi2WO6) on the degradation of phenol which is quite toxic but widely used and slowly degradable in the environment. Almost 97% of the phenol molecules were degraded within 60 min along with the sharp decrease of total organic carbon (TOC) in 100 mL of phenol solution (20 mg/L) under visible-light irradiation. Compared with HR-Bi2WO6 sample, the M-Bi2WO6 sample exhibited a negative shift of conduction band edge potential and faster charge transfer property which helped to improve the photocatalytic performance. (C) 2011 Elsevier B.V. All rights reserved.