Energy gap and impact of change in temperature as core determinant of transport property of ternary NbNiBi Half-Heusler compound

Abstract

This study used Perdew-Burke- Ernzehof-projected augmented wave (PBE-PAW) based on Generalized Gradient Approximation (GGA) to examine the structural and electronic qualities of a new ternary half-Heusler NbNiBi compound. Thermoelectric properties were measured by solving transport theory in Boltz Trap software bundles. The findings revealed optimized lattice constant of 5.96Å, bulk modulus 500kbar, and pressure derivative of 5.00. An indirect energy gap of 2.0eV showcases this material to be a semiconductor type. The energy gap was maintained, the temperature dependence of this compound was calculated from 50⁰K through 350⁰K in steps of 50⁰K. Highest values of Seebeck coefficient (2801.86 µV/K), Fig. of merit (1.01) and electrical conductivity of 3.26 S/ms were recorded at lowest temperature of 50⁰K. The outcome of this work illustrates the potential of NbNiBi material in electronic, engineering, thermoelectricity and its possible innovative uses for further experimental and theoretical considerations.