Promotion of H 2O 2 decomposition activity over β-MnO 2 nanorod catalysts

Abstract

The relationship among the β-MnO 2 nanorod preparation conditions, morphology and catalytic performance on H 2O 2 decomposition has been investigated in the work. β-MnO 2 nanorod catalysts were prepared by heating different γ-MnOOH nanorod precursors at 250–450 °C. They were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen adsorption. The experimental results indicate that γ-MnOOH nanorod precursors prepared at higher hydrothermal temperature make final β-MnO 2 nanorods uniform. The catalytic performance on H 2O 2 decomposition shows that β-MnO 2 nanorod catalysts have excellent catalytic activity on the decomposition of H 2O 2, which has not been reported to our knowledge. β-MnO 2 nanorods which were prepared by calcining γ-MnOOH precursors at 250 °C have higher catalytic activity than those at higher calcination temperatures. The reaction of H 2O 2 decomposition over β-MnO 2 nanorod catalysts was found to follow first-order kinetics.