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Transition metal oxides as a good quasi capacitor materials become hot MnO2 because of its low cost, various preparation methods , wide electrochemical window , the theory is larger than the capacitance and environment-friendly features much researchers pro-gaze . In this paper, α-, β-, δ-, γ-MnO2 and gamma - MnOOH nano-materials for the study , the use of XRD, SEM, TEM, CHI660, Autolab electrochemical workstation and other modern means of testing the structure and properties of the nanomaterials study , the main contents and results are as follows: 1 by hydrothermal method , manganese sulfate and potassium permanganate in the reaction system , by controlling the process conditions , the separately prepared an alpha , beta , gamma , delta four kinds of polymorphs and different forms of MnO2 nanomaterials , in a reaction system to achieve controlled growth of the of MnO2 nanomaterials crystalline phase and morphology . Prepared under alkaline conditions , the layered structure of delta phase MnO2 , its morphology flaky ; under acidic conditions , 2 × 2α -phase , 1 × 1β -phase , 2 × 1γ phase tunnel-like structure is easily formed MnO2 , by changing the reaction temperature , reaction time and the additive content of PVP were prepared in a length of approximately 1 , the alpha phase of approximately 80 nm diameter nanowires ; length of approximately 1 , the diameter of 100 nm of the beta phase nanowires ; gamma- MnO2 nanorods and nanoparticles mixed , and to study the mechanism of change of phase structure under hydrothermal conditions . Finally , on the 140 ° C hydrothermal 10 h and 18 h of a phase nanowires constant current charge-discharge tests , the specific capacity of 41.3 F / g and 13.1 F / g . 2 combined with a micro- emulsion method and hydrothermal method , the use of the surfactant CTAB is formed of soft template , prepared as raw materials to of MnS04 and the KMnO4 a gamma -MnOOH nanowires clusters . gamma - MnOOH diameter of approximately 30 nm and a length of about 2 - 3 micromolar also investigated the hydrothermal reaction before and after different surfactant ( SA and CTAB ) product crystal form , surface morphology , and gamma - MnOOH nanowires clusters forming mechanism ; hydrothermal method , the use of CTAB in water - ethanol system to form a soft template , using the amorphous MnO2 nanowires prepared by gamma -MnOOH , and its length is greater than 1μm diameter of about 200-600 nm . And hydrothermal temperature , hydrothermal time , the template CTAB, the content , the proportion of alcohol-water on the morphology of the gamma - MnOOH . A constant current charge and discharge, cyclic voltammetry , the electrode capacity : 25 F / g on gamma - MnOOH Nano line .
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