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

摘要

Single-crystalline dandelion-like beta-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_2O_2. H_2O_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 Neel temperature of the as-obtained product is 100 K, which is about 6 K higher than that of the corresponding bulk beta-MnO_2 crystals.