Synthesis and characterization of β-MnO2 single crystals with novel tetragonous morphology

{beta}-MnO{sub 2} single crystals with novel tetragonous morphology have been hydrothermally prepared in an HCl solution at 180 deg. C for 24 h without using templates, catalysts, and organic reagents. The structure of the obtained {beta}-MnO{sub 2} was systematically investigated by X-ray diffraction, SEM and TEM microscopy, FT-IR spectroscopy, DSC-TGA analyses, and chemical compositional analyses. The morphology of {beta}-MnO{sub 2} could be controlled by the hydrothermal treatment temperatures and the hydrothermal reaction times. {beta}-MnO{sub 2} single crystals with diameters 200-600 nm and lengths up to 1-5 {mu}m not only had novel tetragonous morphology, but also had high purity.