Facile decolorization of methylene blue by morphology-dependence δ-MnO2 nanosheets -modified diatomite

In this work, coscinodiscus-diatomite and melosira-diatomite have been decorated by ultrathin birnessite MnO 2 (δ-MnO 2 ) nanosheets through a one-pot hydrothermal method without using any surfactants. The δ-MnO 2 nanosheets are observed to grow vertically on the purified melosira-diatomite as well as coscinodiscus-diatomite. Moreover, the two composites exhibit high efficiency for decomposing methylene blue (MB) in the presence of H 2 O 2 . The coscinodiscus-diatmite@MnO 2 achieves a removal rate of 81.8% (2 h), and yet melosira-diatomite@MnO 2 reaches a higher degradation rate of 91.3% in 2 h. Additionally, the effects of catalyst amount, catalysis reaction temperature, preparing time have also been investigated. In principle, the diverse diatomite@MnO 2 nanostructures not only present an environmentally friendly and low cost with a good cycling stability, but also offer a simple way for the catalytic degradation of dye waste water in practical applications.