Microwave Synthesis and Enhanced Thermoelectric Performance of p-Type BiPbCuFeSeO Oxyselenides.

BiCuSeO oxyselenide, one of the best oxygen-containing thermoelectric materials, is promising with great potential applications. In this work, we present a high ZT of >1.3 in BiPbCuFeSeO fabricated microwave synthesis and subsequent spark plasma sintering (SPS). We added 3-4 atom % Fe to the Pb-doped BiCuSeO to regulate the hole carrier concentration and mobility to 0.8-1.0 × 10 cm and ∼40 cm V S, respectively, achieving moderate electrical conductivity, high Seebeck coefficient, and low carrier thermal conductivity simultaneously in a dual-doped sample. Under the synergistic enhancement by stress field, dislocation, and nanophase, the lattice thermal conductivity of BiPbCuFeSeO is limited to 0.24-0.49 W m K at 300-873 K. The development of efficient preparation methods for high-performance thermoelectric materials is significant to promote the application of thermoelectric conversion technology.