Effect of nano CuO sintering aid on densification and microstructure of Gd-doped CeO2

Gd-doped CeO2 powder with chemical composition of Ce0.9Gd0.1O1.95 were synthesized by the solid state method, and then the effect of nano CuO sintering aid (0.5 and 1 mol%) on sintering and microstructure of Gd-doped CeO2 ceramic have been investigated. According to the XRD results, a new phase appears with addition of 1 mol % nano CuO which can be indexed a monoclinic crystalline structure of CuO, i.e., tenorite. The density of the samples improved in the presence of 0.5 mol% nano CuO which can be attributed to the liquid phase formation during the sintering. The spherical shape of porosity in the microstructure of the sample containing nano CuO can results in the liquid phase sintering.