2.1 Catalyst preparation
Firstly, γ-MnOOH nanorod was synthesized by a facile redox precipitation
process. Then the corresponding β-MnO2,
α-Mn2O3 and
Mn3O4 were prepared by calcining γ-MnOOH
nanorods under different temperature and atmosphere. The details of
preparation precedure and chemicals invloved are shown in Supporting
information (SI).