Toward Nanostructured Thermoelectrics. Synthesis and Characterization of Lead Telluride Gels and Aerogels

Journal Article · Thu May 12 04:00:00 EDT 2011 · Journal of Materials Chemistry

DOI:https://doi.org/10.1039/C1JM11015B· OSTI ID:1065266

Ganguly, Shreyashi ^[1]; Brock, Stephanie L. ^[1]

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1. Wayne State Univ., Detroit, MI (United States)

The synthesis and characterization of lead telluride (PbTe) gels and aerogels with nanostructured features of potential benefit for enhanced thermoelectrics is reported. In this approach, discrete thiolate-capped PbTe nanoparticles were synthesized by a solution-based approach followed by oxidation-induced nanoparticle assembly with tetranitromethane or hydrogen peroxide to form wet gels. Drying of the wet gels by supercritical CO₂ extraction yielded aerogels, whereas xerogels were produced by ambient pressure bench top drying. The gels consist of an interconnected network of colloidal nanoparticles and pores with surface areas up to 74 m² g^-1. The thermal stability of the nanostructures relative to nanoparticles was probed with the help of in situ transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The aerogels were observed to sublime at a higher temperature and over a larger range (425–500 °C) relative to the precursor nanoparticles. TGA-DSC suggests that organic capping groups can be removed in the region 250–450 °C, and melting of PbTe nanoparticles occurs near the temperature for bulk materials (ca. 920 °C). The good thermal stability combined with the presence of nanoscale interfaces suggests PbTe gels may show promise in thermoelectric devices.

• Research Organization: Energy Frontier Research Centers (EFRC); Revolutionary Materials for Solid State Energy Conversion (RMSSEC)
• Sponsoring Organization: USDOE SC Office of Basic Energy Sciences (SC-22)
• DOE Contract Number: SC0001054
• OSTI ID: 1065266
• Journal Information: Journal of Materials Chemistry, Journal Name: Journal of Materials Chemistry Vol. 21
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
charge transport
materials and chemistry by design
mechanical behavior
phonons
solar (thermal)
synthesis (novel materials)
synthesis (scalable processing)
synthesis (self-assembly)
thermal conductivity
thermoelectric