51. Effects of S substitution on the structural, optoelectronic, and thermomechanical properties of KTaO3 through density functional theory.
- Author
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Akter, H., Hossain, M.M., Uddin, M.M., Naqib, S.H., and Ali, M.A.
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THERMOMECHANICAL properties of metals , *DENSITY functional theory , *SOLAR energy conversion , *BAND gaps , *OPTOELECTRONICS , *THERMAL conductivity , *OPTOELECTRONIC devices - Abstract
Driven by a curiosity of how sulfur (S) alters the physical properties of KTaO 3 , we embarked on a computational journey using the WIEN2k code and the insights of density functional theory (DFT). We aim to unravel the influence of S-substitution on the material's structure, electronic behavior, optical responses, mechanical strength, and thermodynamic characteristics of KTaO 3. Our investigation has unveiled a remarkable structural transformation, wherein the cubic phase of KTaO 3 undergoes a shift to a tetragonal configuration for KTaO 2 S and KTaOS 2 , eventually returning to a cubic phase in KTaS 3. Significantly, the band gap values have undergone substantial alterations, presenting energy gaps of 1.808 eV, 0.264 eV, and 0.078 eV for KTaO 2 S, KTaOS 2 , and KTaS 3 , respectively, diverging from the original band gap of 3.572 eV in KTaO 3. Importantly, all these compounds have exhibited mechanical and dynamical stability. Furthermore, these compounds have displayed promising optical features characterized by high absorption coefficients (∼105 cm−1), minimal reflectivity (<30%), and robust optical conductivity within the visible spectrum, making them ideal candidates for a range of optoelectronic technologies. Our comprehensive investigation has reinforced the stability of all computed phases, showcasing exceptional electronic, optical, and thermo-mechanical properties, including semiconducting behavior, hardness, ductility, anisotropy, high absorptivity, and low reflectivity. The modified band gap and optical characteristics of KTaO 2 S indicate considerable potential for its application in solar cells, presenting promising opportunities to improve solar energy conversion efficiency. The thermal conductivity of KTaO 3 is fascinating and shows substantial promise for applications as a heat sink material. • The effect of S substitution on the physical properties of KTaO 3 has been studied. • The band gap reduced significantly from 3.572 eV (KTaO 3) to 1.808 eV, 0.264 eV, and 0.078 eV for KTaO 2 S, KTaOS 2 , and KTaS 3. • The band gap and high absorption coefficient of KTaO 2 S indicate its potential for application in solar cells. • The thermal conductivity of KTaO 3 indicates its substantial promise for applications as a heat sink material. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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