Morphological analysis of ultra fine α-MnO2 nanowires under different reaction conditions

• Ultrafine α-MnO2 nanowires with diameter of 10–40 nm and a length up to 0.1–2 μm were synthesized using hydrothermal process.
• A pure tetragonal phase and highly structural symmetry of α-MnO2 were examined using X-ray and IR analysis respectively.
• Study on the morphological changes in the final product under varying reaction time, temperature and nitrite concentration is carried out.

A simple hydrothermal method was developed for the synthesis of ultra fine single-crystal α-MnO2 nanowires by only using potassium permanganate and sodium nitrite in acidic solution, without any seed or template. Detailed analysis of the obtained nanowires was done using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and high resolution transmission electron microscopy (HRTEM) measurements. The as-prepared α-MnO2 nanowires have the average diameter of 10–40 nm and a length up to 0.1–2 µm. Moreover, the effects of reaction temperature, time and reactant molar ratios on the morphology of the final product were studied in detail using field emission scanning electron microscopy (FESEM) measurements.