Hydrothermal synthesis and characterization of α-MnO2 nanostructures

During the past years, there is a growing interest in the study of manganese oxides because of their various applications, for example as important components of solid-state battery systems, and as catalysts for a wide range of industrial catalytic applications and as supercapacitor. Among such oxides, MnO2 is an important class oxide having over 14 polymorphs and is a useful material because it comprises internal tunnel structures with sizes that commensurate with that of cations and thus can act as host lattices for the insertion and extraction of cations[1].Hydrothemal synthesis has been an interesting technique to prepare materials with different nanoarchitectures such as nanowires, nanorods, nanobelts, nanourchins and so forth. The main advantages of the hydrothermal technique over other soft chemical routes are the abilities to control tha nanostructures ranging from nanoparticles to nanorods or nanourchins to nanotubes by properly choosing the temperature or time of the reaction or the active fill level in the pressure vesel or solvent used for the reaction without any major structure-directing agents or templates[2].In this work we report the synthesis of MnO2 single crystal nanostructures with α-crystallographic phase by hydrothermal method and consider crystalographic and morphological properties of resulted products. Also we will consider the effect dwell time of hydrothemal reaction in crystalinity nature and morphological properties of resulting nanostructured materials in hydrothermal method