Crystal structures, effective masses, electronic and optical properties of KTa₅O₁₃ and KTaO₃: A density functional theory study

The crystal structure, electronic and optical properties of KTa₅O₁₃ and KTaO₃ were studied by first-principles calculation based on density functional theory (DFT). The band structures show that both KTa₅O₁₃ and KTaO₃ are indirect band gap. Then the calculated effective masses of holes and electrons shows that the carrier mobility of KTa₅O₁₃ is low, while that of KTaO₃ is high. Besides, In order to further explore the transparent conductivity and photocatalytic performance the position of band edge and optical properties are analyzed. The analysis indicates that KTa₅O₁₃ and KTaO₃ are transparent to visible light, and predict whether KTaO₃ is a good transparent conductive material. Moreover, KTa₅O₁₃ and KTaO₃ are predicted to have good photocatalytic activity.