Novel dandelion-like beta-manganese dioxide microstructures and their magnetic properties.

Single-crystalline dandelion-like β-MnO(2) three-dimensional microstructures have been successfully prepared for the first time via a simple hydrothermal process based on the direct reaction between Mn(NO(3))(2) and H(2)O(2). H(2)O(2) plays an important role in the formation of the dandelion-like morphology. The formation mechanism of the dandelion-like nanostructures was investigated and discussed based on the experimental results. Magnetic measurements show that the Néel temperature of the as-obtained product is 100 K, which is about 6 K higher than that of the corresponding bulk β-MnO(2) crystals.