Photocatalytic reduction of CO2 to methanol by three-dimensional hollow structures of Bi2WO6 quantum dots

Three-dimensional hollow structures made up of Bi2WO6 quantum dots were prepared by one-pot solvothermal synthesis using ethylene glycol as reactive solvent. The structural, optical and CO2-photoreduction to methanol of these hollow structures were investigated. The ethylene glycol is important not only in assembling the three-dimensional hollow structures but also in suppressing the agglomeration of Bi2WO6 quantum dots. The hollow structure of Bi2WO6 quantum dots has a much higher CO2 adsorption capacity and a wider band gap than does bulk-Bi2WO6, so that the CO2 photoconversion reaction is much faster for the hollow structures made up of Bi2WO6 quantum dots.