Thermoelectric properties of Half-Metallic FeMnScGa Using First Principle Calculation

Abstract: Here, we have investigated the thermoelectric properties of FeMnScGa alloy by combined use of full potential linearized augmented plane-wave (FP-LAPW) method and Boltzmann transport theory implemented in Wien2K and BoltzTraP code, respectively. Using the TB-mBJ potential, half-metallic nature is clearly observed with energy band gap of ~0.41 eV for down spin channel. Transport coefficients in 200-1000 K temperature range are investigated under the constant relaxation time approximations (tau=10-14 s). Total contributions to the Seebeck coefficients from up and dn-spin channels are estimated by using two-current model. The calculated values of Seebeck coefficients are found to be negative in the entire temperature region under present study, which suggests the n-type characteristic of this alloy. The magnitude of Seebeck coefficient is found to be increasing with temperature and exhibit the large value ~ -87 micro-V/K in 700-1000 K temperature range. The maximum in magnitude of total electrical conductivity value is found to be ~2.0 x 105 ohm-1m-1 at 1000 K. The present study shows, with half-metallic electronic structure, FeMnScGa have very good thermoelectric behavior, and can be suitable for thermoelectric application in high temperature region.