Synthesis and charge storage properties of templated LaMnO3–SiO2 composite materials

Mesoporous LaMnO3 with bulk surface areas in the range 225-300 m2 g-1 were prepared by direct overgrowth around the short-channel version of SBA-15 silica. The extent of LaMnO3 growth was found to be affected by the polarity of solvent system used to impregnate the SBA-15 with La3+ and Mn2+ precursors. The resulting LaMnO3-SiO2 composites were stable in refluxing NaOH, suggesting that the SiO2 was fully encapsulated. The composites were structurally characterized using a range of techniques including 2-D elemental mapping and Raman spectroscopy. The electrochemical behavior of the composites was tested for pseudocapacitance, which revealed normalized specific capacitances over 200 F g-1.