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FIZIKA A 19 (2010) 4 , 183-190
 
MORPHOLOGY-CONTROLLED POWER FACTOR OF NANOSTRUCTURED BISMUTH TELLURIDE
DIPALI BANERJEEa, KRISHANU CHATTERJEEa, ABHIJIT PALa,
N. R. BANDYOPADHYAYb, SUDIP K. BATABYALc, CHITRA BASUc,
G. S. SANUALd and A. R. DASe
aDepartment of Physics, Bengal Engineering and Science University, Shibpur, Howrah 711103, India
bSchool of Materials Science, Bengal Engineering and Science University, Shibpur, Howrah 711103, India
cDepartment of Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
dDepartment of Chemistry, University of Kalyani, Kalyani, Nadia, India
ePolymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
Received 31 October 2009; Revised manuscript received 27 October 2010
Accepted 24 November 2010 Online 6 April 2011
Bismuth telluride is a thermoelectric material with
high figure of merit, used for cooling applications
at room temperature. To investigate the effect of
morphology and grain size on transport parameters,
nanostructured bismuth telluride has been synthesized
under different reaction conditions and characterized
by X-ray diffraction, transmission electron microscopy
and scanning electron microscopy. From the measurement
of electrical conductivity and thermoelectric power,
power factor for different samples has been obtained.
The results show that the transport parameters are
critically influenced by the morphology and dimension
of the samples that in turn depend on the condition of
synthesis. The experimentally observed variation of
electrical conductivity with the change of dimensionality
of the samples from 2D to 0D, which is in line with the
theoretical prediction made by other workers, is
discussed. There is a variation of the power factor of
the samples prepared under different conditions of
synthesis.
PACS numbers: 72.20.Dp, 72.20.Pa
UDC 537.323
Keywords: nanostructures, semiconductors, X-ray dispersive analysis, thermoelectric effects
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