2024/04/01 by Susmita Chowdhury, Niraj K. Singh, Chowdhury, Susmita +11 · 1 citation
Engineering · Physics and Astronomy · #FOS: Physical sciences #Intermetallics and Advanced Alloy Properties #Materials Science (cond-mat.mtrl-sci) #Rare-earth and actinide compounds #Thermodynamic and Structural Properties of Metals and Alloys
paper · pdf · doi:10.48550/arxiv.2404.01417
openalex publication_date 2024/04/01 · openalex created_date 2024/04/05 · openalex updated_date 2026/08/01
The electronic structure of Sc1-xVxNy epitaxial films with different alloying concentrations of V are investigated with respect to effects on thermoelectric properties. Band structure calculations on Sc0.75V0.25N indicate that V 3d states lie in the band gap of the parent ScN compound in the vicinity of the Fermi level. Thus, theoretically the presence of light (dispersive) bands at the Γ-point with band multiplicity is expected to lead to lower electrical resistivity while flat (heavy) bands at X-W-K symmetry points are associated with higher Seebeck coefficient than that of ScN. With this aim, epitaxial Sc1-xVxNy thin film samples were deposited on MgO(001) substrates. All the samples showed N substoichiometry and pseudocubic crystal structure. The N-vacancy-induced states were visible in the Sc 2p XAS spectra. The reference ScN and Sc1-xVxNy samples up to x = 0.12 were n type, exhibiting carrier concentration of 1021 cm-3, typical for degenerate semiconductors. For the highest V alloying of x = 0.15, holes became the majority charge carrier as indicated by the positive Seebeck coefficient. The underlying electronic structure and bonding mechanism in Sc1-xVxNy influence the electrical resistivity, Seebeck coefficient, and Hall effect. Thus, the work contributes to the fundamental understanding of the correlated defects and thermoelectric properties to the electronic structure in Sc-N system with V alloying.