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21st Century nanomaterials has broad application prospects. Which manganese oxide nanomaterials because of their unique electronic structure and has the advantage of no other oxides. In the electronics industry, magnetic, chemical, catalytic, environmental and other fields are widely used. The valence of manganese and more complex structure oxide variety. Therefore, the study of manganese oxide nanomaterials preparation and effective regulatory factors has important significance. This article was prepared by oxidation precipitation method were nano Mn 3 O 4 , MnOOH and core-shell magnetic nanomaterial Fe 3 O 4 / FeMnO x , effects of preparation conditions on the material structure and morphology, and studied its electrochemical properties and catalytic oxidation. This article consists of the following three aspects: (1) Preparation of nanometer oxide precipitate Mn 3 O 4 and MnOOH nano-precipitation method using oxidized Mn 3 O 4 , the effects of temperature, NaOH addition rate, additives, sodium dodecylbenzenesulfonate (SDBS) and reactant dosing methods of reaction conditions on product structure morphology. The results showed that: the product increases with increasing temperature crystallization and ripening; adding SDBS conditions, NaOH dropping rate of only affect Mn 3 O 4 morphology, but also restricting the different phases Mn 3 O 4 and MnOOH formation. When the slow drip of NaOH (1ml / L), the product of Mn 3 O 4 nanoparticles; when the fast drip rate of NaOH (6ml / L) , the product is Mn 3 O 4 nanorods; Pour off when NaOH, the product was MnOOH nanorods. Adding SDBS, NaOH drip rate 6ml / L under the conditions of the reactants NaOH and H 2 O 2 also determines the order of addition of the product types. To join the H 2 O 2 , the product of Mn 3 O 4 nanorods; while when first adding NaOH , the product is MnOOH nanorods. (2) additives on Mn 3 O 4 morphology with Mn (NO3) 2 and NH3 · H 2 O as precursor, H2O2 as oxidant, prepared a series of Mn 3 O 4 nanoparticles explores nine kinds of additives on the product particle size. Including: tartaric acid, citric acid, glucose, EDTA, oxalic acid, polyethylene glycol, glutamic acid, ethanol, and CTAB. The results showed that: tartaric acid, citric acid and glucose on the product Mn 3 O 4 has a great impact on the size. The greater the amount added to the smaller size of the product; and Mn 3 O 4 surface area and capacitance as the particle size decreases significantly increased. (3) core-shell structure of manganese complexes Nanomaterials and its catalytic performance were prepared by co-precipitation of uniform size, with a ferromagnetic Fe 3 O 4 , particle size of about 30-50nm. Then the impregnation and the external cladding layer of oxidation manganese composite oxide, a dipping process control certain pH. End up with a core-shell structure Fe 3 O 4 / FeMnO x Fe-Mn oxides. With Fe 3 O 4 compared, Fe 3 O 4 / FeMnO x surface hydroxyl groups has a richer and greater electron transfer capability, which has better performance. Experimental results show that the active material in a wide pH range can effectively catalyzed H 2 O 2 degradation of methylene blue in water, the reaction mechanism is adsorbed onto the catalyst surface organics by H 2 O 2 decomposition of · OH further oxidation removal.
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