Effect of bismuth tungstate with different hierarchical architectures on photocatalytic degradation of norfloxacin under visible light

The photocatalytic degradation of norfloxacin by bismuth tungstate (Bi2WO6) with different hierarchical architectures was investigated under visible light irradiation. Bi2WO6 was prepared by hydrothermal method with the reaction solution pH ranging from 4 to11. The relatively ultrathin Bi2WO6 nanoflakes prepared at pH 4 showed excellent adsorption and photodegradation efficiency towards norfloxacin. The characterization results showed that Bi2WO6 prepared at pH 4 had a larger specific area and faster photo-generated carrier separation rate. The decay rate reached the maximum in weak alkaline reaction solution, which could be attributed to the presence of moderate OH- anions. The present study demonstrated that the smaller size of Bi2WO6 could be an efficient photocatalyst on the degradation of norfloxacin in the aquatic environment.