Cerium oxide is a inorganic compound substance, chemical formula is CeO2, light yellow or yellowish brown auxiliary powder. Density 7.13g/cm3, melting point 2397 ºC, insoluble in water and alkali, slightly soluble in acid. At a temperature of 2000 ºC and a pressure of 15MPa, cerium oxide can be reduced by hydrogen to obtain cerium trioxide.
When the temperature is free between 2000 ºC and the pressure is free at 5MPa, cerium oxide appears slightly yellow with red color and pink color. Its performance is to be used as polishing materials, catalysts, catalyst carriers (additives), ultraviolet absorbers, fuel cell electrolytes, automotive exhaust absorbers, electronic ceramics, etc.