Influence of Heavy Hf Doping in Ceo2 : Prediction on Various Physical Properties Via Density Function Theory Approach

This work employs density functional theory to calculate the structural, mechanical, elastic anisotropy, thermal, electronic, and optical properties of Ce 1-x Hf x O 2 (x = 0, 0.25, 0.5, and 0.75) to explore the heavy substitutional doping effects of Hf. The cubic phase of CeO 2 is transformed to tetragonal when 50% Ce is replaced by Hf. The thermodynamic and mechanical stability of all doped phases are manifested by the calculated formation energy and elastic constants, respectively. The present calculation demonstrates the ductile behavior of pure and all doped phases of CeO 2 , among which the tetragonal Ce 0.5 Hf 0.5 O 2 is more ductile than that of other phases. Similarly, this tetragonal phase exhibits highest anisotropic nature among all the studied phases, which is confirmed by studying the various anisotropy indices. Interestingly, the pure and doped phases of CeO 2 are acceptable for thermal barrier coating, however doping with 75% Hf at Ce-site makes it even more suitable. The semiconducting nature of CeO 2 is evolved because of having band gap in the electronic band structure, which is supported by its experimental report. The band gap is increased with the increment of Hf doping level. The optical absorption and conductivity reconfirm the semiconducting nature of the studied materials. Furthermore, the optical functions suggest the potential applications of Ce 1-x Hf x O 2 in microelectronics, integrated circuits, and solar panel