First-principles relativistic analysis of Dy-doped CdSe: Electronic band structure, optical properties, and thermoelectric potential for PC-LED applications

Abstract

This study performed relativistic first-principles calculations, using the GGA+U+SOC method within density functional theory (DFT), to investigate the effects of Dy doping in CdSe. Electronic, optical and thermoelectric properties were explored using the Wien2k code for doping concentrations of 3.125 % (Dy-CdSe) and 6.25 % (2Dy-CdSe). Dy doping converted CdSe from a semiconductor to metallic materials. Formation energy calculations showed that all materials are thermodynamically stable. The optical properties demonstrated enhanced features in low energy range which is desirable for optoelectronic materials. With testing the thermoelectric properties, the analysis showed Dy doping suppressed the electrical conductivity as well as, the thermal conductivity. Finally, the figure of merit (ZT), peaked with a value of 15.1 × 10⁻³, which shows great potential for making PC-LEDs and thermoelectric devices which utilize energy efficiency.