One-pot hydrothermal synthesis of β-MnO2 crystals and their magnetic properties

β-MnO2 nanorods and flower-like structures were synthesized via a one-pot hydrothermal route at 160 °C without using any template and surfactant. It is demonstrated that H+ in the solution has a significant effect on the morphology and resultant magnetic property of β-MnO2 crystals. Magnetic measurements indicate that the Néel temperature of the β-MnO2 flower-like structures is 98 K, which is about 2 K higher than that of the nanorods counterpart.