Bismuth oxyhalide quantum dots modified sodium titanate necklaces with exceptional population of oxygen vacancies and...

We here demonstrate the controlled synthesis of BiOBr quantum dots (QDs) decorated Na₂Ti₃O₇ necklaces via a hydrothermal transformation of sodium titanate nanotubes. The BiOBr QDs are deposited on the surface of Na₂Ti₃O₇ necklaces, forming a heterogeneous interface of BiOBr(200) and Na₂Ti₃O₇(110), which promotes the separation efficiency of photogenerated charges, thus resulting in its superior catalytic performance in the photo-oxidation of benzyl alcohol. The BiOBr/Na₂Ti₃O₇-1.0 exhibiting highest oxygen defect population gives best photocatalytic activity with a promising conversion rate of 3.32 mmol_{reacted BA} g_catal.^-1h^-1, which is substantially higher than the corresponding reported photocatalysts. DFT results corroborate the superior performance of BiOBr/Na₂Ti₃O₇ is mainly due to the formation of a built-in electric field and given efficiently the charge transfer between BiOBr(200) and Na₂Ti₃O₇(110). In all, this study reports a simple in-situ hydrothermal growth protocol to efficiently construct BiOBr/Na₂Ti₃O₇ heterojunction composites and offers guidelines for design of a new synthetic strategy to prepare efficient photocatalysts.