Thermoelectric properties of BiCuSO doped with Pb

BiCuSeO based oxide show excellent thermoelectric performance due to its low thermal conductivity and moderate Power factor. There is rare study on the same crystal structured BiCuSO with lower cost and more earth abundance. The thermoelectric performance of BiCuSO is limited by its high resistivity result from its low carrier concentration and large band gap. In this paper, p-type polycrystalline BiCuSO doped with Pb was fast prepared by one-step high pressure method and the composition dependent thermoelectric properties was studied. The electrical resistivity and Seebeck coefficient of Bi1-xPbxCuSO both decreased monotonically with increasing Pb content due to the increased carrier concentration. The power factor was improved and the thermal conductivity was suppressed by Pb doping. The maximum figure of merit, ZT similar to 0.14 @ 700 K was obtained for the Bi0.975Pb0.025CuSO sample, which makes them promising candidates for thermoelectric applications.