Design and controllable synthesis of α-/γ-Bi2O3 homojunction with synergetic effect on photocatalytic activity

A α-/γ-Bi2O3 composite has been successfully prepared via a hydrothermal method. The as-prepared nanocrystals are characterized by the X-ray diffraction, Fourier transformation infrared spectrum, Scanning electron microscopy, Transmission electron microscopy, and high-resolution transmission electron microscopy examination. The homojunction between the α-Bi2O3 and γ-Bi2O3 is confirmed by the diffuse reflectance spectra and impedance spectrum. The photocatalytic activities of the samples were evaluated by the degradation of Rhodamine B as a model pollutant. The composite exhibited higher photocatalytic activity than bare α-Bi2O3 or γ-Bi2O3 in the degradation of RhB. The enhanced photocatalytic activity is attributed to the synergetic effect of the homojunction.

► Design and synthesis of α-/γ-Bi2O3 homojunction.
► The α-/γ-Bi2O3 homojunction possess the highest photocurrent and photocatalytic activities.
► The characterization of the existence of α-/γ-Bi2O3 homojunction.
► Synergic effect between α-Bi2O3 and γ-Bi2O3 in the composite.