Synergistically boosting of CO2 photoreduction over Bi/BiOBr nanostructure via in-situ formation of oxygen vacancy and metallic Bi

Depositing metal on the surface of semiconductor has been deemed to be an valid tactics to heighten the reducing activity of photocatalyst. Herein, the Bi/BiOBr catalyst was prepared via NaBH4-assisted reduction reaction. The photocatalytic capacity of CO2 conversion for Bi/BiOBr was appraised. The optimal Bi/BiOBr exhibits that the production rates of CO and CH4 are 251.2 and 25.6 & mu;mol g-1h-1 individually, being 12.3 and 8.9 times as high as original BiOBr. The excellent activity for Bi/BiOBr could be put down to the synergy of surface plasmon reso-nance (SPR) effect of metallic Bi and OVs in the surface of BiOBr. More importantly, the OVs on surface of BiOBr could be deemed as reactive locations for the adsorption of CO2 and H2O molecules. This work reveals the synergistic effect of in-situ formed OVs and metal nanoparticles of Bi on enhancing the photocatalytic activity.

Automated summary

Depositing metal on the surface of semiconductor is an effective strategy to enhance the reducing activity of photocatalyst. In this study, Bi/BiOBr catalyst was prepared via NaBH4-assisted reduction reaction and its photocatalytic capacity for CO2 conversion was evaluated. The optimal Bi/BiOBr showed significantly higher production rates of CO and CH4 compared to original BiOBr, attributed to the synergy of surface plasmon resonance effect of metallic Bi and oxygen vacancies in the surface of BiOBr. The oxygen vacancies on the surface of BiOBr can be considered as reactive locations for CO2 and H2O molecules adsorption. This work reveals the synergistic effect of in-situ formed oxygen vacancies and metal nanoparticles of Bi on enhancing the photocatalytic activity.