Fe-ions modified mesoporous Bi2WO6 nanosheets with high visible light photocatalytic activity

Fe-ions modified mesoporous Bi2WO6 nanosheets (Fe-Bi2WO6) were successfully synthesized via a simple two-step method, which involved a template-free hydrothermal process and a following impregnation treatment. The resultant products were characterized by XRD, TEM, XPS, EDX, ESR, UV-Vis, PL, and visible light photocatalytic measurements. Experimental results indicated that the addition of a small amount Fe-ions (optimized content at 0.1 wt.%) could evidently improve the activity of Bi2WO6. The apparent reaction rate of Fe-Bi2WO6-0.1% (k, 0.099 min(-1)) was 3.2 times higher than that of Fe-(BiWO6)-W-2-0% (k, 0.031 min(-1)). The Fe-ions mainly existed as Fe3+ and Fe2+ ions, which were uniformly distributed on the surface of Bi2WO6 nanosheets and some Fe3+-ions substituted Bi3+-ions in Bi2O2 layers. Both of the concentration and state of Fe-ions played vital factors for the improved visible light photocatalytic activities. (C) 2011 Elsevier Inc. All rights reserved.