  The stability, electronic structure, optical and thermoelectric properties of
Te-doped BaTiO3 are investigated by first-principal calculation based on the
density functional theory and Boltzmann transport theory implemented in WIEN2K
and BoltzTraP simulation program. This study is carried out by applying LDA +
TB-mBJ potential. Formation energy of each doped structure is calculated to
examine the stability and feasibility of the synthesis. Incorporating Te into
BaTiO3 efficiently reduces the electronic band gap and the level of band gap
reduction can be controlled by varying the amount of dopant. Hence, the
absorption ability is improved in the visible light. Our findings suggest that
all the doped structures are significantly absorbent and productive with an
optical absorption that exceeds 105 cm-1 in the visible range. In addition,
BaTiO3 revealed a smaller dielectric constant at zero frequency compared to Te
doped-BTO: 8.3%, while the optical energy gap is reduced from 3.692 eV to 1.619
eV by growing Te concentration. Then, optical conductivity and Urbach's
parameters are predicted. The transport properties are assessed as a function
of temperature. It is found that the electrical conductivity is considerably
enhanced with increase properties such as Seebeck coefficient and figure of
merit are also investigated. Our theoretical results can be useful for
thermoelectric and visible light photoelectrical device applications.
