Water oxidation catalysis by using nano-manganese ferrite supported 1D-(tunnelled), 2D-(layered) and 3D-(spinel) manganese oxides

Abstract

We report a new series of core-shell composite catalysts obtained by supporting 1D-(tunnelled), 2D-(layered) and 3D-(spinel) manganese oxides on nano-manganese ferrite. All other factors being equal, magnetic 2D-MnOx structures carried out the chemical water oxidation reaction with Ce4+ at a higher efficiency than their 1D-, 3D- and non-magnetic counterparts. Ca-birnessite, when supported on a ferrite core, produced the highest amount of O-2 [3900 mmol (O-2) per mot (Mn) per hl normalized per mot of manganese in the catalysts. The composition and morphology parameters of the magnetic core-shell structures appeared to be important in determining the observed activity while no direct correlation was noted with the surface area.