Unravelling Optoelectronic and Transport Properties in RuZrX (X=Si, Ge) Alloys: Insights from DFT

The structural, mechanical, electronic, and thermoelectric properties of RuZrSi and RuZrGe half-Heusler alloys were thoroughly examined using the full-potential linearized augmented plane-wave (FP-LAPW) method within the WIEN2k code, based on Density Functional Theory (DFT). The study utilized the Perdew-Burke-Ernzerhof generalized gradient approximation (GGA-PBE) and the Tran-Blaha-Johnson (TB-mBJ) approximations for the exchange-correlation potential. The findings reveal that both alloys are semiconductors with indirect band gaps, and they are ductile, anisotropic, and mechanically stable. These properties make them suitable for various practical applications. The electronic analysis confirms the semiconducting nature of RuZrSi and RuZrGe due to their indirect band gaps. Mechanically, both alloys show ductility and stability, enhancing their potential usability. Additionally, their thermoelectric properties are notable, with high Seebeck coefficients (S) and a significant figure of merit (ZT), indicating strong performance in thermoelectric devices. Optical properties, including the dielectric function and absorption coefficients, suggest these materials have considerable potential for photovoltaic and optical applications, especially in the UV and visible light spectrum. While these results are promising, experimental validation is required to confirm the theoretical predictions made in this study.