Top-down synthesis of sponge-like Mn3O4 at low temperature

摘要

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.