Computational investigation of Ba2ZrTiO6 double perovskite for optoelectronic and thermoelectric applications.

In recent years, double perovskite oxides have been considered as highly promising electrode materials, with use in different energy production applications. Proposing new perovskite solid solutions, however, is a great challenge due to the analytical complexity introduced by disorder. Here, we investigate the structural formability and electro-optical properties of the possible Ba 2 ZrTiO 6 double perovskite which can be also considered as a solid solution of BaZrO 3 and BaTiO 3 perovskites. Based on our calculations, by considering the (τ) − tolerance factor and the (μ) -octahedral factor, the Ba 2 SrTiO 6 double perovskite exhibits a perfectly cubic structure with the space group Fm3m (space group no: 225). Our electrical properties calculations show that Ba 2 ZrTiO 6 is a direct semiconductor with a Γ point band gap about 3.14 ​eV obtained with the modified Becke-Johnson (mBJ) approximation. We also discovered remarkable optical properties of the proposed double perovskite. Furthermore, the effect of hydrostatic pressure in the 0–35 ​GPa range on the electronic properties of the compound is investigated. It was found that the hydrostatic pressure slightly increases the energy gap of the material while the band gap remains direct (Γ to Γ). Also, the optical spectra experience blue shifts under pressure. Analyzing the thermoelectric features shows that the material exhibits a good Seebeck coefficient and thermoelectric power factors which suggest this structure as a promising material for thermoelectric applications. The results suggest Ba 2 ZrTiO 6 double perovskite for use in electrical, optical and thermoelectric applications. [Display omitted] • Ba2ZrTiO6 double perovskite shows a cubic structure with the space group of Fm3m. • Ba 2 ZrTiO 6 double perovskite is a mechanically stabile structure and shows brittle property at its ground state. • Ba2ZrTiO6 double perovskite shows a Γ point direct band gap of about of 3.14 ​eV. • Ba2ZrTiO6 double perovskite shows interesting strain tunable electrical and optical properties. • Ba2ZrTiO6 double perovskite shows a good Seebeck coefficient and power factor. [ABSTRACT FROM AUTHOR]