Manganese Oxide Nanoparticles
Manganese dioxides have drawn great attention due to their excellent physicochemical properties, rich structural variety, low cost and environmental friendliness. There are various polymorphic forms of manganese dioxides including alpha, beta, delta and gamma due to the different linkways of the primary unit [MnO6] octahedra. Different structures of MnO2 exhibits distinct activities and thus separate application. For the use of electrochemical energy storage and conversions such as secondary batteries and supercapacitors, alpha and gamma MnO2 are of particular interest because their structures contain 1-dimensional channels, which is considered to be more accessible and the most active. Manganese oxide nanoparticles display interesting electronic and magnetic properties due to changes in their structure and bonds. Along with the size-finite effects, some magnetic properties of these materials, like the spontaneous magnetization, the Curie temperature and anisotropic energy are very affected by the particle size. The key applications of manganese oxide nanoparticles are biosensors, coatings, nanowires, nanofibers, as a magnetic-nanoparticles for magnetic data storage and magnetic resonance imaging (MRI), etc.