Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 6, Issue 6, Pages 3995-4004Publisher
AMER CHEMICAL SOC
DOI: 10.1021/am405410e
Keywords
resonant states; coherent nanostructures; lattice thermal conductivity; band offset; thermoelectric figure of merit
Funding
- CSIR through CSIR NET
Ask authors/readers for more resources
Motivated by the theoretically predicted Zn resonant states in the conduction band of PbTe, in the present work, we investigated the effect of Zn substitution on the thermoelectric properties in I-doped n-type PbTe. The room temperature thermopower values show good agreement with the theoretical Pisarenko plot of PbTe up to a carrier concentration of 4.17 X 10(19) cm(-3); thus, the presence of Zn resonance levels is not observed. Because of the low solubility of Zn in PbTe, a second phase of coherent ZnTe nanostructures is observed within the PbTe host matrix, which is found to reduce the lattice thermal conductivity. The reduced lattice thermal conductivity in PbTe by ZnTe nanostructures leads to notable enhancement in the figure of merit with a maximum value of 1.35 at 650 K. In contrast to the recent literature, the carrier mobility is not found to be affected by the band offset between ZnTe nanostructures and PbTe. This is explained by the quantum tunneling of the charge carrier through the narrow offset barrier and depletion width and coherent nature of the interface boundary between the two phases, i.e., ZnTe and PbTe.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available