In situ construction of rich oxygen vacancy Bi/Bi3TaO7 heterojunction photocatalysts

Oxygen vacancy-rich Bi/Bi 3 TaO 7 binary nanomaterials were obtained by a simple in situ reduction . The as-prepared composite exhibited superior photocatalytic activity for the degradation of RhB compared to the single material under the visible light range. The degradation rate of the optimal sample reached 92% within 120 min, 12.25 times that of the pure Bi 3 TaO 7 . XRD and HRTEM characterization showed that the Bi metal obtained through in situ reduction was loaded on the Bi 3 TaO 7 nanostructure. In addition, XPS and EPR indicated a significant increase in the oxygen vacancy content of the composites. The time-resolved transient fluorescence spectroscopy and photocurrent results proved that the separation rate of photoexcited carriers and the corresponding ability of photoelectrons are greatly increased. It is due to the synergistic effect of the unique photo-reaction excitation pathway induced by bismuth metal plasma resonance and oxygen vacancies, which not only extends the photo-reaction to the infrared region but also increases the carrier residence time, and this is the fundamental reason for the excellent photocatalytic performance of the composite material. The h + is the main reactive radical of the reaction, and •O 2 − also plays a role. Based on the above characterization study, we propose a possible photoreaction mechanism for the synergistic oxygen vacancy and Bi metal of Bi/Bi 3 TaO 7 .