1D and 3D MnO₂ for catalytic oxidation of organic pollutants

Recently, sulfate radicals generated from peroxymonosulfate (Oxone®, PMS) or persulfate (PS) have been applied as an alternative to hydroxyl radicals. Neither homogeneous Co²⁺/PMS nor heterogeneous catalysis utilizing supported cobalt oxides can completely avoid the leaching or loss of cobalt ions, thus resulting in secondary metal pollution.(Liang et al., 2012) Manganese oxides are abundant in soils and have various forms such as MnO, MnO₂, Mn₂O₃ and Mn₃O₄. Due to variation of the oxidation states between 2+ and 4+ redox cycles, manganese oxides have excellent oxygen mobility in the oxide lattices and thus induce superior redox reactions. In this study, 1D and 3D shape-controlled manganese oxides were prepared and employed to activate peroxymonosulfate to produce sulfate radicals for catalytic oxidation of organic pollutants. The mechanism was also discussed. (author)