Improving Effect of MnO₂ Addition on TiO₂-Photocatalytic Removal of Lead Ion from Water

Abstract

Removal of Pb (II) ions from water was carried out by a coupling approach of adsorption and photoelectrodeposition over a porous TiO₂ photocatalyst loaded with MnO₂. The addition of MnO₂ onto the porous TiO₂ accelerated the photocatalytic oxidation of Pb (II) ions, which was caused by a strong interaction between MnO₂ and Pb (II) ions. Since the same effect was not observed on the photocatalytic degradation of methylene blue over MnO₂/TiO₂ photocatalysts, the photoelectrodeposition reaction rate appears to be determined by the amount of Pb (II) ions adsorbed on the surface of porous TiO₂ loaded with MnO₂.