The conductivity and TEMF of MoS2 with Mo2S3 additive

Transition-metal chalcogenides are prospective thermoelectric materials. One of them is a molybdenum disulfide MoS₂, which has a layered structure. MoS₂ has a good potential to have a high value of thermoelectric quality factor due to a high value of thermo-EMF and low value of thermal conductivity. But a low value of its electrical conductivity suppresses the thermoelectric quality factor ZT on the level of 0.1 at high temperatures. Present work shows the influence of metal addition to MoS₂ on electrical conductivity and Seebeck coefficient (SC) of final mixture. Mo₂S₃ was chosen as a metal addition. Mo₂S₃ has an electrical conductivity of 330 S/m and thermo-EMF of 10 μV/K at 300K. Bulk powder samples of MoS₂ with addition of 3, 6, 10, 30 and 60 wt% Mo₂S₃ were studied. An electrical conductivity of samples was measured in temperature range: 77 K - 423 K. All samples have shown semiconductor hopping conductivity with variable hopping length. The SC was measured in the temperature range of 300K - 500K. The addition of Mo₂S₃ decrease SC from 300μV/K to 75μV/K.