High durability, stability, effective thermoelectric and thermodynamic properties of NbFePb half-Heusler compound

Abstract

We examined structural, electronics, elastic, mechanical and thermodynamic properties of an innovative NbFePb compound using the ultrasoft pseudopotential and nonlinear core correction functional type of Perdew-Burke-Ernzenhof as specified in Quantum Espresso soft bundles in line with density functional theory with the atomic framework of Generalized Gradient Approximation. The transport behaviours were determined by engaging semi-classical Boltzmann transport theory as detailed in Boltz Trap code. The calculated lattice constant is 5.50Å. The computed electronic band structure has an indirect energy gap of 1.4 eV between points Γ and X revealing a semiconductor compound. Total and partial density of states were explored and this reflect the dominance of Pb p-atom. The high value of ratio of bulk modulus to shear modulus (5.01), Poisson ratio (0.44), and positiveCauchy’s pressure (239.49GPa) indicate durability and capacity of this material to resist deformation under stress.NbFePb is an anisotropic compound with universal anisotropic greater than one. Debye temperature of 296.48K was recorded. NbFePb compound exhibited esteemed value of Seebeck coefficient 2516.96µV/K at 300K, premium power factor of 21.02 x10¹⁰W/msK² at 800K and Fig. of merit 21.09 also at 800K. This makes this material to have a high-potential for thermoelectric purposes