Nanostructure-Assisted Phonon Scattering in Lead-Free Thermoelectric Materials: A TEM Investigation of the SnTe System
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چکیده
We have used HRTEM and STEM EDX to determine the important roles of endotaxial nanostructures in a lead-free thermoelectric (TE) material, SnCd0.03Te, with 2% CdS and 2% ZnS; where maximum ZTs of ~1.3 and ~1.1 are achieved at 873 K, respectively. TE materials convert wasted heat into electric energy. The conversion efficiency of TE materials is characterized by a dimensionless figure of merit ZT = S 2 T/ κ , where S is the Seeback coefficient, σ is the electrical conductivity, T is the absolute temperature and к = ке + κ ι is the total thermal conductivity, including both electronic (ке ) and lattice (κ ι) contributions. The record-high ZT values resulting from nanoscale precipitates in p-type SnTe make SnTe-based materials ideal candidate for p-type lead chalcogenides [1-3] for high temperature thermoelectric power generation.
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تاریخ انتشار 2014