摘要

Sol-gel combustion method has been used as an efficient and simple method to synthesize pure Ca2Co2O5 (CCO-225) ceramic powder using sucrose which play a dual role as the gelling agent and combustion fuel. The advantage of this method is simple low cost and environmental friendly. The synthesized sample is sintered at various temperatures the products were characterized by powder X-ray diffraction (XRD), Thermogravimetric and differential thermal analysis (TGA-DTA), Fourier transformer infrared spectroscopy (FTIR), Scanning electron microscope (SEM) and UV-Visible diffuse reflectance spectroscopy (DRS). X-ray diffraction pattern of sintered sample at 800 degrees C confirmed the formation of single phase Ca2Co2O5 and also it is proved in thermal analysis. SEM image indicates the obtained samples are diffused platelet like morphology and its grain size will be in the range of 150-300 nm. CCO-225 ceramic material has a wide range of optical and electronic applications due to its wide band gap energy of 3.50 eV. The dielectric constant, dielectric loss and AC conductivity were analyzed at different temperatures and frequencies of the applied field. The AC conductivity studies carried out in the frequency range of 50 Hz to 5 MHz at various temperatures from 30 degrees C to 400 degrees C. The result reveals that the space charge polarization leads for conduction mechanism.

  • 出版日期2014-5