Fabrication of BiO2-x@TiO2 heterostructures with enhanced photocatalytic activity and stability

A unique core-shell structured BiO2-x@TiO2 heterojunction has been fabricated by a two-step method. In the heterojunction, 2D nanosheets are evenly covered by amorphous TiO2. The existence of TiO2 not only increases the specific surface area, but also improves the separation and transfer of photogenerated charge carriers, and meanwhile it also effectively protects BiO2-x@TiO2 from photo-corrosion. As a result, BiO2-x@TiO2 heterojunction exhibits a superior photocatalytic activity and stability toward the degradation of methyl orange (MO) and H-2 evolution. Thus, BiO2-x@TiO2 heterojunction can be a promising visible-light photocatalyst in the field of environmental remediation and solar energy conversion.