Computational investigation of the phase stability and reactivity of CoCuFeNiZn high-entropy alloy

Abstract

This study investigates the phase stability and reactivity of CoCuFeNiZn high-entropy alloy (HEA) through computational and heuristic approaches. We find that computed lattice parameters of various CoCuFeNiZn compositions closely align with experimental data for face-centered cubic (fcc) structures. Employing modified Hume-Rothery (HR) rules tailored for HEAs, we confirm the stability of bulk CoCuFeNiZn HEA as a single-phase fcc solid solution, supported by consistent atomic radius differences (δ_r), electronegativity differences (Δχ), and valence electron concentrations (VEC) across all compositions. Further validation of the bulk CoCuFeNiZn HEA as stable fcc solid solutions is achieved using criteria such as the Ω parameter and enthalpy of mixing (ΔH_mix). Additionally, our investigation into oxygen (O) adsorption reveals strong binding on the CoCuFeNiZn HEA surface, suggesting promising catalytic applications.