Effect of Reducing Agent NaBH₄ on Photocatalytic Properties of Bi/BiOBr/Bi₂WO₆ Composites

Abstract

With the improvement of human living standards, a large amount of drugs in the fields of medicine, agriculture, animal husbandry and other fields have being invested and used, resulting in an increasing demand for cleaning antibiotics to clean water sources. In this study, Bi/BiOBr/Bi 2 WO 6 composite photocatalyst was successfully synthesized by ahydrothermal method with BiOBr as the precursor. The effect of reducing agent sodium borohydride (NaBH 4 ) on the structure and photocatalytic activity of the composite was studied. The results showed that most active photocatalyst was obtained when 20 mmol/L of sodium borohydride was used. The degradation of norfloxacin on Bi/BiOBr/Bi 2 WO 6 reached 96.1%, which was about 6.7% higher than that on BiOBr/Bi 2 WO 6 . And the reaction rate was 1.4 times of BiOBr/Bi 2 WO 6 . The heterojunction formed by the three substances was the main reason for the enhanced catalytic activity. These results were beneficial for the practical application of high performance Bi/BiOBr/ Bi 2 WO 6 photocatalytic materials.

Hydrothermal Synthesis, Formation Mechanism and Photocatalytic Activity of SnO2/BiOBr

“…Furthermore, the SnO 2 /BiOBr‐4 composite exhibits the widest range of light absorption, suggesting that its light absorption performance is better, which is beneficial to photocatalytic. The band gap energy (Eg) of the sample can be obtained by combining UV‐vis DRS and the formula α hν=(hν– E g ) 1/2 , [24–27] as shown in Figure 5 (b). The band gap energys of BiOBr, SnO 2 , SnO 2 /BiOBr‐1, SnO 2 /BiOBr‐2, SnO 2 /BiOBr‐3, SnO 2 /BiOBr‐4 and SnO 2 /BiOBr‐5 are 2.93 eV, 3.72 eV, 2.91 eV, 2.89 eV, 2.87 eV, 2.78 eV and 2.82 eV, respectively.…”

“…Furthermore, the SnO 2 /BiOBr-4 composite exhibits the widest range of light absorption, suggesting that its light absorption performance is better, which is beneficial to photocatalytic. The band gap energy (Eg) of the sample can be obtained by combining UV-vis DRS and the formula αhν = (hν-E g ) 1/2 , [24][25][26][27] as shown in Figure 5 The light absorption performance of SnO 2 /BiOBr was compared with that of the binary complex composed of other compounds combined with BiOBr, and the results were shown in Table 1. Compared with several common BiOBr-based binary complexes, SnO 2 /BiOBr-4 has the best light absorption performance, which may be related to the superior electrical conductivity of SnO 2 .…”