Facile synthesis of manganite nanowires: Phase transitions and their electrocatalysis performance

In this paper, ultrathin (about 2.5nm) manganite (MnOOH) nanowires were synthesized by a simple wet chemical method at ambient temperature. Temperature-dependent phase transition patterns of the prepared nanowires under different atmospheres were systematically studied with thermogravimetric and differential thermal analysis (TG/DTA). Based on the critical temperatures demonstrated by the phase transition pattern, manganese oxides, such as Mn ₂O₃ and Mn₃O₄, have been obtained conveniently through calcination. Scanning electron microscope(SEM), transmission electron microscope(TEM) and x-ray diffraction results confirm that the annealed nanowires can both retain their original 1D morphology and show good crystallinity. The electrocatalytic performance of the as-prepared manganese oxides was also explored, which showed good response to the reduction of H₂O₂ in alkaline media. Among the three manganese oxides, the MnOOH nanowires exhibited the most prominent electrocatalytic efficiency and stability, which provides a good candidate for modern industrial catalysis applications.