THERMOELECTRIC MATERIALS AND THEIR PROPERTIES

Abstract

Seeing today’s scenario, it can easily be depicted that the time will come when the human race will witness the shortage and extinction of non-renewable natural resources due to their abundance use in today’s time. So, to keep this thing in mind, many scientists turn their focus towards some promising alternatives of fossil fuels, and thermoelectric material is one of them. This work presented a first-principles-based investigation pertaining to the analysis of the effect of Hf doping on thermoelectric properties of half Heusler alloy RhTiP. The energy bandgap of RhTiP is 0.810 eV. With increase in the concentration, the bandgap became less for RhTi0.75Hf0.25P and increased for all other doping concentrations, the energy bandgap rise linearly with doping concentration. At 100% doping of Hf, i.e., for RhHfP, it is observed to be 1.464 eV. Here the material showed the highest thermoelectric performance at 100% doping of Hf in place of Ti (RhHfP) at room temperature, while other resultant compounds after the doping were also showing good thermoelectric behaviour. The maximum value of power factor and electrical conductivity at room temperature were 0.19688x1012 WK −2m−1 s −1 and 3.2058*1018Ω −1m−1 s −1which belong to RhHfP. The maximum ZT

value came out to be 0.7950 at room temperature, which is again of RhHfP.