화학공학소재연구정보센터
Materials Research Bulletin, Vol.73, 385-393, 2016
Sol-gel synthesis and enhanced photocatalytic activity of doped bismuth tungsten oxide composite
Pristine Bi2WO6 and Bi2WO6/Bi14W2O27 photocatalysts were synthesized by sol-gel method using Co(II) cation as dopant. The influence of Co dopant to the formation of Bi2WO6/Bi14W2O27 heterostructure composite was discussed. The photocatalytic activities of as-prepared samples were evaluated sufficiently by using rhodamine B as target organic pollutants under visible light. The as-prepared Bi2WO6/Bi14W2O27 heterostructure achieved enhanced optical absorption in the visible-light region, and exhibited much higher photocatalytic activities than that of pristine Bi2WO6. The optimum Bi/Co molar ratio and calcining temperature were also explored. The enhanced activities were attributed to the formation of heterostructure in suppressing the recombination of photo-generated carriers. The Co dopant species would participate to reduce the charge carrier recombination by acting as trapping sites for photogenerated charges. A possible photocatalytic mechanism over Bi2WO6/Bi14W2O27 heterostructure was proposed. (C) 2015 Elsevier Ltd. All rights reserved.