Enhanced thermoelectric figure of merit through electrical and thermal transport modulation by dual-doping and texture modulating for Ca3Co4O9+δ oxide materials

The realization of high figure of merit for thermoelectric materials relies on modulating the electrical and thermal transport at the same time. In this work, the Ca3Co4O9+δ oxide based material specimens with regulated carrier transport, phonon transport as well as enhanced figure of merit are prepared through barium and praseodymium dual doping and spark plasma sintering. The bulk specimen shows the largest figure of merit 0.31 at 973 K for Ca2.8Ba0.1Pr0.1Co4O9+δ bulk specimen due to improved power factor and suppressed thermal conductivity. The combining effect of dual doping is indeed positive for optimizing the thermoelectric performance for the titled oxide materials.146