Crystal growth and thermoelectric properties of Sn-doped Bi2Se3

We have studied the crystal growth of Sn x Bi 2 Se 3 ( x  = 0 ∼ 0.75) and examined the effect of Sn doping on the structure and thermoelectric properties of Bi 2 Se 3 . All the crystal samples of Sn x Bi 2 Se 3 were synthesized using a direct melt-growth. The results indicated that when the Sn doping content was ≤ 0.3, some Sn atoms were incorporated into the interlayers of Bi 2 Se 3 , thereby increasing the carrier concentration. In the intermediate to the high-temperature range, Sn doping improved the electrical conductivity of Bi 2 Se 3 , resulting in overall good performance in the power factor( PF ). All the doped samples exhibited good ZT (a dimensionless figure of merit) in the intermediate to the high-temperature range, especially with the doping sample of  x   = 0.3 showing a maximum ZT value of 0.2 at 835 K.