Top-down synthesis of sponge-like Mn(3)O(4) at low temperature

A top-down synthetic method was developed for the fabrication of sponge-like Mn(3)O(4) composed of Mn(3)O(4) nanocrystals by decomposition of manganese formate at 200 °C. The samples were characterized in terms of their structural and morphological properties by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) studies. TEM and SEM images showed that the morphology of sponge-like Mn(3)O(4) structures was mostly retained from the morphology of the manganese formate precursor, which was controlled by the solvothermal process. Large sponge-like Mn(3)O(4) structures exhibiting crystallographic symmetry were prepared under solvothermal treatment for a long time. The XRD pattern showed that the Mn(3)O(4) exhibit a tetragonal hausmannite structure. The results of N(2) adsorption analysis indicated that the sponge-like Mn(3)O(4) nanostructures possess high surface area. The possible formation mechanism of Mn(3)O(4) nanostructures has been discussed.