Synthesis of Ca₃Co₄O₉ Powder by EDTA Complexing Sol-Gel Method

Ca₃Co₄O₉ is a novel kind of material with mid and high temperature thermoelectric properties.With acetates and ethylene-diamine-tetraacetic-acid(EDTA) as raw materials,Ca₃Co₄O₉ powders were synthesized by EDTA complexing sol-gel method at lower temperature.Ca₃Co₄O₉ powders were characterized by means of thermogravimetry-differential scanning calorimeter(TG-DSC),X-ray diffraction(XRD),Fourier transformation-infrared(FT-IR) spectroscopy,scanning electron microscopy(SEM) and energy dispersive X-ray analysis(EDX).The results show that the single phase Co₃Co₄O₉ powders can be obtained after the xerogel calcined at 700-900℃ for 2h and the Ca₃Co₄O₉ powders were sheet-like crystals with the average size of 100~200 nm.