Optimized thermoelectric performance via Li doping to regulate electrical transport in rock-salt-structured high-entropy (MgCoNiCuZn)O ceramics

The effect of Li doping on the thermoelectric properties of a rock-salt phase high-entropy (MgCoNiCuZn)O ceramic has been investigated. The starting (non-doped) ceramic exhibits a high Seebeck coefficient, but the low associated electrical conductivity constrains overall thermoelectric performance. Following Li doping, the ceramics retain a stable single-phase rock-salt structure with a significant increase in electrical conductivity while preserving a high Seebeck coefficient. The sample with 10 at% Li doping achieved the highest thermoelectric efficiency, with a power factor ten times higher than the non-doped sample. The findings of this study demonstrate that Li doping effectively enhances the thermoelectric performance of (MgCoNiCuZn)O ceramics, making them suitable candidates for medium-high temperature applications.