Self-assembled mesoporous manganese oxide with high surface area by ambient temperature synthesis and its enhanced electrochemical properties

Self-assembled mesoporous γ-MnO2 was synthesized via ambient temperature redox synthesis. The X-ray diffraction pattern of the sample annealed at 200 °C confirmed the formation of pure phase of γ-MnO2. FE-TEM studies revealed a 1-D nanostructure formed from aggregates composed of nanowire crystallites with diameters and lengths ranging from 2–3 and 25–40 nm respectively. An average pore size of 3.77 nm with a type IV isotherm which confirmed the mesoporous characteristics and a high surface area of 148 m2/g were estimated by the N2 adsorption/desorption and Brunauer–Emmett–Teller (BET) studies respectively. The mesoporous γ-MnO2 electrode in a Li/MnO2 cell registered initial discharge capacity of 268 mAh/g with a well-defined plateau around 3 V.

Graphical abstractEnhanced electrochemical performance of template/surfactant-free or self assembled mesoporous – MnO2 prepared by ambient temperature synthesis.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Direct synthesis of template/surfactant-free mesoporous γ-MnO2 by ambient temperature reactions. ► The self assembled mesoporous γ-MnO2 possessed high surface area and exhibited enhanced electrochemical properties. ► This low-cost synthesis is useful for the large-scale production of alternative mesoporous metal oxides.