  (Bi1-xSbx)2Te3 (x=0.60, 0.65, 0.68, 0.70, 0.75 and 0.80) mixed crystals have
been synthesized by solid state reaction. In depth structural, thermal,
transport and electronic properties are reported. Defect and disorder play a
crucial role in structural and transport behaviour. Disorder induced
iso-structural phase transition is observed at x=0.70, which is supported by
the structural and transport properties data. Debye temperature has been
estimated from the powder diffraction data. Differential scanning calorimetry
(DSC) data confirms the glass transition in the material. Low temperature
resistivity data shows Variable range hopping mechanism whereas high
temperature data follows activated behaviour. Activation energy is calculated
from the semiconducting region of resistivity data. Both Hall measurement and
temperature dependent thermopower data (S(T)) confirms that samples are p-type
in nature. Density of state effective mass has been estimated from Pisarenko
relation and corroborated with resistivity data. Thermal conductivity (k) is
estimated using experimentally obtained data. Figure of Merit (ZT) of the
synthesized samples are calculated using resistivity, S(T) and k. Structural
and transport properties are correlated, confirms the transition from disorder
to order state. Defect and disorder are corroborated with structural and
Thermoelectric properties of the synthesized samples.
