Mesoporous BiVO4/TiO2 heterojunction: enhanced photoabsorption and photocatalytic ability through promoted charge transfer

BiVO 4 has been constructed into heterojunctions with TiO 2 to boost the photocatalytic ability under visible illumination. Here, mesoporous BiVO 4 /TiO 2 nanocomposites have been fabricated by a facile sol–gel approach utilizing nonionic surfactant and addressed for morphological, optical, structural, and degradation of ciprofloxacin (CIP) in water under visible illumination as an antibiotic pollutant model. The TEM images demonstrated that the TiO 2 NPs are homogenous in terms of shape and size (15 ± 5 nm). The introduction of BiVO 4 into mesoporous TiO 2 could effectively enhance the rapid separation efficiency of the photoinduced carriers and optical absorption. The 3%BiVO 4 /TiO 2 photocatalyst possessed the best degradation efficiency (100%) within 60 min which was promoted 20-folds larger than TiO 2 NPs (5%). 3%BiVO 4 /TiO 2 nanocomposite exhibited the fastest degradation rate (2.15 × 10 −2 min −1 ), which was 40 times faster than bare TiO 2 photocatalyst (0.05 × 10 −2 min −1 ). The enhanced photocatalytic ability originated from superior charge separation characteristics and high solar energy absorption in mesopore structures. The recombination rate and mobility of charge carriers were characterized utilizing photoluminescence (PL) and photoelectrochemical measurements. This work highlights the advantages of mesoporous heterojunction BiVO 4 /TiO 2 nanocomposites for photocatalytic performances and provides a multilateral route to design an effective wide-spectrum response photocatalyst for the development of comparable materials. The photocatalytic mechanism for degradation CIP over BiVO 4 /TiO 2 was discussed in detail. .