Abstract
We report the electronic structure, optical and charge transport properties of the unexplored ternary Zintl phases KCuX(X=Se,Te) from the first principles calculations employing the full-potential linearized augmented plane-wave (FLAPW) method with the Tran Blaha modified Becke-Johnson (TBmBJ) potential. It is demonstrated that the materials are direct band gap (1.13, 1.38 eV) semiconductors with covalent bonding between Cu and (Se/Te). The calculated low effective mass and high carrier mobility (over 105 cm2/V.s) accentuate that KCuX have good carrier transport and the materials may have possible applications in solar cell absorbers and nanoelectronic devices. Absorption spectra indicates that the ternary crystals are UV-A light absorbers and could be useful in photovoltaic and photodetector applications. A study on the effect of pressure (till 5 GPa) is carried out in order to further explore the materials for their electronic band gaps and charge transport properties as they are proposed to be useful in future contemporary electronic devices. It is observed that pressure enhances the intrinsic carrier mobility and thermal stability of KCuX, indicating that the materials can withstand robust external conditions.
Highlights
Semiconductors with narrow band gap have been of great interest since last four decades for their fundamental physics and utility in infrared devices, LEDs, infrared lasers and thermophotovoltaics[1]
Present ternary Zintl phases KCuX(X = Se, Te) fall into the category of valence precise compounds and these compounds were synthesized at 973 K and 1073 K respectively[5]
The presently dealt ternary Zintl phases KCuX were synthesized by Savelsberg and Schfer in 19785
Summary
Semiconductors with narrow band gap have been of great interest since last four decades for their fundamental physics and utility in infrared devices, LEDs, infrared lasers and thermophotovoltaics[1]. In some layered crystal structures, efficient mixing of Cu and chalcogenide takes place at the top of the valence bands. Huge efforts have been made in search of semiconductors with moderate band gaps, high carrier mobility and thermal stability for potential applications in photonic devices and nanoelectronics. We aim to present a theoretical insight into the structural, electronic, charge transport and optical properties of ternary KCuX with efficient TBmBJ potential by including spin-orbit interaction in the ab initio calculations. This study offers a fertile testing ground for the exploratory work on more unexplored intermetallic Zintl phases of this kind
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
