Exploring the Physical and Optoelectronic Properties of Co 2 ZrZ Compounds: Insights from Computational Analysis and Thermoelectric Characterization

Abstract

The current study examines the physical properties of Co2ZrZ compounds (Z= Pb, Bi and As) using the Wien2k calculation code. The Anisimov and Gunnarsson approach is used to calculate the Hubbard parameters for Cobalt (Co) and Zirconium (Zr). The results indicate that Co2ZrBi and Co2ZrAs have metallic characteristic, however Co2ZrPb displays semi-metallic behaviour. The energy gap calculations provide values of 0.328 eV (GGA) and 1.102 eV (mBJ-GGA) in the G-X-direction. The valence bands of Co2ZrBi and Co2ZrAs are primarily influenced by the Co-D-eg and Co-D-t2g states in both spin channels. Infrared transitions with energy levels below 0.56 eV indicate a decrease in the ability of electrons to move, which is compensated by an increase in ultraviolet absorption. The Co2ZrZ compounds have potential for space solar energy applications as they possess the ability to absorb UV light and improve conductivity. The effective ultraviolet (UV) absorption of Co2ZrPb has the potential to be advantageous for satellites and space missions. Within the high-energy range, the refractive index decreases to a value below one, which signifies "Super-luminescence". Additionally, plasmatic oscillations have a further impact on optics. The thermoelectric investigation of Co2ZrPb using BoltzTraP code reveals a predominance of P-type charge carriers, suggesting a high level of electrical conductivity and a low resistance. The ZT values of Co2ZrPb oscillate between 0.99 (at 50 K) and 0.84 (at 1500 K), which are close to unity, this indicates that Co2ZrPb is appropriate for thermoelectric applications.