Enhanced Thermoelectric Properties Through Carrier Scattering by Localized Nano-Magnetism

Thermoelectric energy conversion has a lot of attention because of its simple and convenient energy conversion of heat to electricity. In this work, the thermoelectric energy conversion efficiency was enhanced in huge amount by introducing nano-magnetic impurity. The localized spin moment of nano-magnetic impurity interacts with conduction electron spin, resulting scattering of conduction electron. The scattering changes the energy dependence of electron scattering time, inducing decoupling of Seebeck coefficient(<i>S</i>) and electrical conductivity(<i>σ</i>). In general, the <i>S</i> and <i>σ</i> are coupled and limit the enhancement of thermoelectric conversion efficiency. The powerfactor(<i>S</i>²<i>σ</i>) was enhanced in whole temperature range, thus the thermoelectric figure of merit, <i>zT</i> was enhanced up to 1.8 at 923 K in Mn doped SnTe nanocomposite. The sophisticated theoretical analysis about electron scattering was conducted using Boltzmann transport equation.