CHARACTERISTICS OF LaCrO3 NANOMATERIAL THE EFFECT OF THE CALCINATION TEMPERATURE

LaCrO3 nanomaterial is prepared using simultaneously the sol-gel and the freeze-drying method. Nitrate salts of lanthanum and chrome are dissolved in a pectin solution. The sample is thoroughly stirred using a magnetic stirrer while adjusting pH to 11 until a gel is formed. After the freeze-drying process, the precursors are subjected to a calcination treatment at 600°C,700°C, and 800°C and subsequently characterized by X-ray diffraction(XRD), TEM and DRS analyses. The results verify that a major crystalline phase of LaCrO3 perovskite is formed as the temperature of calcination increases. The crystallites size identification using the Scherrer equation shows that the size increases with calcination temperature increase. But the grain size analysis by TEM verifies that the calcination temperature has in fact a small effect on the size. The DRS analysis indicates that the band-gap energy is affected by the calcination temperature. The values obtained increase from 2.62 eV to 2.89 eV and 2.98 eV with temperature increase.