Title: Visible-light CO2 photocatalytic reduction performance of ball-flower-like Bi2WO6 synthesized without organic precursor: effect of post-calcination and water vapor



The crystal phase and composition of as-prepared catalysts wereanalyzed using with an X-ray diffractometer (X’Pert PRO, PANa-lytical Co., Japan) with Cu K _ irradiation. Field emission scanningelectron microscopy (FE-SEM) images were recorded to study themorphology of the samples with a scanning electron microscope(SIRION-100, FEI Co., USA). The specific surface areas were deter-mined with a static adsorption instrument (JW-BK 132F, Beijing JWGB Sci & Tech Co., China) by the Brunauer–Emmett–Teller (BET)method and the pore distribution curves were obtained by the BJH desorption method.