The Preparation of Cu - doped Ca₃Co₄O₉ Thermoelectric Materials

In this paper, CaCO₃, CoO, CuO as raw materials, using solid phase preparation of Ca₃Co₄O₉-based thermoelectric materials doping Cu. The Ca₃Co₄O₉-based thermoelectric material intermediates were prepared according to the stoichiometric ratio x=0.01, and the sintered crystals were prepared by using muffle furnace under different temperature setting conditions. X-ray diffraction (XRD) and Scanning electron microscopy (SEM) were used to analyze the crystallinity and morphology of the samples after sintering. The results show that the crystallinity of Ca₃Co₄O₉-based thermoelectric materials is best when sintered at 800-850°C, and the crystallinity of samples sintered at 850°C is better than that at 800°C, The diffraction intensity ratio is stronger than 800°C. Continue to raise the temperature, Ca₃Co₄O₉-based thermoelectric materials phase transition to Ca₃Co₂O₆-based thermoelectric materials, When the sintering temperature is 1000°C, the product is Cu-doped Ca₃Co₂O₆-based thermoelectric materials.