The Effect of Metal Ions as Dopants on OMS-2 in the Catalytic Degradation

Abstract

Here we first designed, synthesized and compared Ni, Ag and Ce doped manganese oxide octahedral molecular sieves, (Ni-OMS-2, Ag-OMS-2 and Ce-OMS-2) for the catalytic degradation of organic dyes, such as reactive red 2, acid orange 7, methylene blue, and rhodamine B, in the presence of potassium peroxymonosulfate in aqueous solutions. These results show that the catalytic efficiency increases in the order of Ce-OMS-2 < OMS-2 < Ag-OMS-2 < Ni-OMS-2 for organic dyes degradation, which is in accordance with the concentration of oxygen vacancy defects on the surface of materials. Then pH condition and various amounts of Ni-OMS-2, organic dye and potassium peroxymonosulfate concentration have also been investigated for the reactive red 2 degradation. In addition, TEM and XRD have confirmed the heterogeneous catalyst Ni-OMS-2 has been successfully recycled at least 5 times with a very slight reduction efficiency by the simple filtration. We have designed, synthesized and compared Ni, Ag and Ce doped OMS-2, (Ni-OMS-2, Ag-OMS-2 and Ce-OMS-2) for the degradation of organic dyes. And they show the catalytic efficiency increases in the order of Ce-OMS-2 < OMS-2 < Ag-OMS-2 < Ni-OMS-2 for the degradation.