Sol–gel synthesis and characterization of mesoporous manganese oxide

Mesoporous manganese oxide (MPMO) from reduction of KMnO4 with maleic acid, was obtained and characterized in detail. The characterization of the material was confirmed by high-resolution transmission electron microscopy (HRTEM), X-ray powder diffractometry (XRD) and N2 sorptometry. The results showed that MPMO is a pseudo-crystalline material with complex network pore structure, of which BET specific surface area is 297 m2/g and pore size distribution is approximately in the range of 0.7–6.0 nm. The MPMO material turns to cryptomelane when the calcinating temperature rises to 400 °C. The optimum sol–gel reaction conditions are KMnO4/C4H4O4 molar ratio=3, pH=7 and gelation time>6 h.