Seebeck coefficient, figure of merit, power factor, and electronic fitness function as vital tools for assessing thermoelectric behaviour of MnNip compound by first principle approach

This work engaged Perdew-Burke-Ernzehof for solid (PBEsol) within the framework of Generalised Gradient Approximation based on Density Functional Theory as its exchange correlation functional as found in Quantum Espresso pseudopotential library to examine structural and electronic qualities of ternary semiconductor half-Heusler MnNiP compound. Structural evaluation indicates optimised lattice constant of 5.29Å, volume of 250.488a.u3 , bulk modulus 500 Kbar and pressure derivative of 4.99. A direct energy gap of 0.3 eV from W→W, k-vector path was observed. Electronic transport properties were explored using Semi-Classical Boltzmann Transport Theory as expressed in the Boltz Trap code. High values of Seebeck coefficient (1292.85 µV/K) as it varied with chemical potential and electronic fitness function (10.85 W5/3ms-1/3K-2 ) as a function of hole were reported at 800 K. This material is a future prospect for a sustainable thermoelectric generation.