One-step synthesis of sea urchin-like α-MnO2 using KIO4 as the oxidant and its oxidation of arsenite

Among several types of manganese oxides alpha-MnO2 is the most active due to its good catalytic, adsorption and ion exchange properties. Sea urchin-like alpha-MnO2 particles were synthesized by a one-step chemistry route at room temperature using MnSO4 in combination with KIO4 as oxidant. The obtained alpha-MnO2 was characterized using X-ray powder diffraction (XRD), structure refinement, electron microscopy and N-2 gas adsorption and used to investigate the property of the As (III) oxidation. Results revealed that the space group of the prepared product is I-4/m with lattice constants a = 9.840 angstrom and c = 2.856 angstrom, and the average grain diameter is around 6.7 nm. The BET surface area is 201 m(2).g(-1). Its maximum oxidation capacity of arsenite is up to 1086 mmol.kg(-1). (C) 2012 Elsevier B.V. All rights reserved.