Multistep synthesis of AgBr quantum dots coupled porous BiOBr spheres for enhanced photocatalysis

Abstract

A three-step route has been adopted for the synthesis of AgBr quantum dots coupled porous BiOBr spheres. Firstly, porous Bi spheres were obtained through a simple solvothermal method employing ethylene glycol as a reducing agent. Sequentially, a redox reaction of Bi spheres with NH4Fe(SO4)2 as an oxidiser was employed to prepare porous BiOBr spheres. Finally, AgBr quantum dots were loaded on BiOBr spheres through in situ precipitation. The obtained powders were characterised by employing powder X-ray diffraction for phase confirmation and transmission electron microscopy for microstructure evolution. BiOBr hierarchical spheres with a diameter of ca. 500 nm were made up by two-dimensional nanosheets. AgBr quantum dots were deposited on BiOBr petals and did not influence the microstructure and morphology of the BiOBr host. The BiOBr/AgBr composite exhibited higher photocatalytic activity than pure BiOBr porous spheres in degrading Rhodamine B dyes.