Soft chemistry synthesis of CaMnO3 powders and films

Calcium manganite, CaMnO3, was prepared by two autocombustion methods and by coprecipitation. The crystallization of CaMnO3 from raw powders was studied by X-ray diffraction, Fourier transform infrared spectroscopy and thermal analysis methods. The morphology and purity of the obtained CaMnO3 powders was found to depend on the synthesis method. CaMnO3 films were deposited by a doctor blade, and optical and electrical properties of both powders and films were investigated and correlated to their morphology. CaMnO3 powder prepared by the autocombustion citrate method had the highest electrical conductivity. The optical band gap for all CaMnO3 powders was determined to be in the 1.1-1.2 eV range. These properties make CaMnO3 suitable for use as an active layer and a potential candidate for composite photovoltaic materials.