Fabrication and thermoelectric properties of Ga1-xInxSb compounds by solid reaction

III-V compounds with the zinc blende structure possess high carrier mobility and good power factors due to their unique crystal and electronic structure. In this work, In-doped GaSb (Ga1-xInxSb, x = 0, 0.02, 0.05, 0.1, 0.15, 0.2) were fabricated by combining melting method with SPS sintering technique. The microstructure and thermoelectric properties of Ga1-xInxSb compounds were systematically studied. Experimental results indicate that by introducing In into Ga sites, the lattice thermal conductivity has been effectively reduced by substituting Ga with In, resulting in a ZT value increases from 0.01 to 0.17 (600 K) when x = 0.02. However, further increase of In doping dosage leads to the decrease of power factors, and therefore the decrease of ZT values.