As the proportion of MWNTs in the composite further increased, the degradation efficiency gradually decreased. This could be due to that more MWNTs might block the pores of the composites and reduce the active sites of Bi2WO6. As a result, the photodegradation efficiency of the photocatalyst decreased . Thus the 3% MWNTs–Bi2WO6 was selected for the following study.
To illustrate the impact of hybridization of MWNTs with Bi2WO6 on the photodegradation of TC, the photodegradation efficiency of the 3% MWNTs–Bi2WO6 was compared with other materials, including the physical mixture of Bi2WO6 and 3% MWNTs, anatase, rutile and P25 TiO2.