Enhanced visible light photocatalytic performance of a novel heterostructured Bi4Ti3O12/BiOBr photocatalyst

Abstract

A novel Bi₄Ti₃O₁₂/BiOBr heterojunction photocatalyst was successfully fabricated for the first time through a traditional solid state method combined with a successive in situ growth method. The as-formed BiOBr nanosheets with diameters in the range of 100–200 nm were embedded homogenously on the surface of Bi₄Ti₃O₁₂ particles. The photocatalytic activity was evaluated by degradation of pure silk dyeing wastewater and antibiotics (ciprofloxacin and tetracycline) under visible light (λ > 400 nm). The Bi₄Ti₃O₁₂/BiOBr heterojunction photocatalyst has a higher photocatalytic activity than pure Bi₄Ti₃O₁₂ and BiOBr. The Bi₄Ti₃O₁₂/BiOBr composite presented a significantly improved ability of Acid Blue dye and antibiotic photodegradation, which is almost 1.3 and 1.5 times higher than that of pure Bi₄Ti₃O₁₂ and BiOBr, respectively. The enhanced photocatalytic activity can be attributed to the effective separation of photo-generated electron–hole pairs driven by the p–n junction formed in heterostructured Bi₄Ti₃O₁₂/BiOBr.