Selective hydrothermal synthesis of BiOBr microflowers and Bi2O3 shuttles with concave surfaces

Through controlling the amount of NaOH added, BiOBr and Bi2O3 with different shapes were hydrothermally synthesized in the reaction system of Bi(NO3)3-hexadecyl trimethyl ammonium bromide (CTAB)-NaOH. As 8 mmol of NaOH was added, BiOBr microflowers constructed of nanoflakes were synthesized. The thickness of these single-crystal nanoflakes was about 20 nm. In the similar condition, when the amount of NaOH added was 28 mmol, Bi2O3 shuttles with concave surfaces were obtained. The length of these shuttles was 100 μm and the diameter at the middle of these shuttles was 50 μm. The photocatalytic activity of as-prepared BiOBr microflowers was evaluated by the degradation of methyl orange (MO) under visible-light irradiation (λ>420 nm), which was up to 96% within 90 min.

Graphical abstractThrough controlling the amount of NaOH added, BiOBr microflowers and Bi2O3 shuttles with concave surfaces were hydrothermally synthesized in the reaction system of Bi(NO3)3-hexadecyl trimethyl ammonium bromide (CTAB)–NaOH.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► BiOBr microflowers constructed of nanoflakes were synthesized hydrothermally. ► Bi2O3 shuttles with concave surfaces were also synthesized. ► Their formation mechanisms were studied based on the experimental results. ► The photocatalytic activity of BiOBr microflowers was evaluated under visible-light irradiation.