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Growth and magnetic properties of MnO2−delta nanowire microspheres

J. B. Yang·X. D. Zhou·W. J. James·S. K. Malik·C. S. Wang
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Abstract

We report the synthesis of MnO2−delta microspheres using hydrothermal and conventional chemical reaction methods. The microspheres of MnO2−delta consist of nanowires having a diameter of 20-50 nm and a length of 2-8 micro m. The value of the oxygen vacancy delta estimated from the x-ray photoelectron spectrum (XPS) is 0.3. The magnetization versus temperature curve indicates a magnetic transition at about 13 K. It is found that a parasitic ferromagnetic component is imposed on the antiferromagnetic structure of MnO2−delta, which might result from distortion of the lattice structure due to oxygen vacancies. The magnetic transition temperature TN is about 10 K lower than that of the bulk MnO2 single crystal.

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J. B. Yang, X. D. Zhou, W. J. James, S. K. Malik, C. S. Wang. 2004-09-14. Growth and magnetic properties of MnO2−delta nanowire microspheres. https://doi.org/10.1063/1.1805699

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