A DFT + U study of cerium solubility in La2Zr2O7

Density functional theory plus Hubbard U correction is employed to study the solubility of cerium in La2Zr2O7. The results show that La2Zr2O7 and Ce2Zr2O7 form a solid solution over the whole range of cerium content. The solubility of Ce in La2Zr2O7 can be partially attributed to the similar ionic radii of La3+ and Ce3+. Electronic structures of the La2−yCeyZr2O7 solid solution have been analyzed. The Ce 4f states are found to be partially occupied, and Ce in the La2−yCeyZr2O7 solid solution exhibits a reduced charge state.