Thermoelectric transport in heterogeneous medium: The role of thermal boundary resistance

To investigate the effect of thermal boundary resistance (TBR) on thermoelectric transport, the discontinuity in temperature is considered at the interface through Kapitza's definition. The effect depends on two factors: the length of thermoelectric element and the value of TBR. More importantly, it is found that TBR has dramatic impact on the reduction in thermoelectric conversion efficiency, which decays exponentially with increasing TBR. The ratio of thermal boundary resistance to the length of thermoelectric element leading to the decrease of effective Seebeck coefficient largely accounts for the degradation of thermoelectric performance at the micro-scale.