Spatially confined growth of Bi2O4 into hierarchical TiO2 spheres for improved visible light photocatalytic activity

摘要: Bi2O4 is a promising visible light responsive photocatalyst but its application limited by the large particle size and fast recombination rate of charge carriers. Herein, flower-like hierarchical TiO2 sphere with rich mesorpores macropores was used as framework for space-confined growth nanosized Bi2O4, creating enormous Bi2O4/TiO2 type II heterojunctions enlarging interfacial contract areas between TiO2. Benefitting from these outstanding features, photocatalytic activity heterojunction degradation methyl orange much higher than that pure under light. The greatly improved separation efficiency carriers derived shortened transfer distance photogenerated charges interior to surface nanoscaled are responsible enhanced performance. In addition, radical capture experimental results imply hole dominant reactive species orange.