Microstructure and Thermoelectric Properties of Na_0.5CoO₂

Abstract:

The polycrystalline of sodium cobalt oxide (Na_0.5CoO₂) was synthesized by solid state reaction method and sintering method. The microstructure was composed of powder size and crystal structure. The Seebeck coefficient and electrical resistivity are measured. We found that the concentration of sodium ions sandwiched between two neighboring CoO₂ layers played a crucial role in transport properties. The results showed small particle size, single phase and orthorhombic structure. The Seebeck coefficient of Na_0.5CoO₂ increased as the temperature increased. The electrical resistivity was decreased as temperature decreased from the range 300-500 K.

• Periodical: Advanced Materials Research (Volume 802)
• Pages: 218-222
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.802.218
• Online since: September 2013
• Authors: Wanatchaporn Namhongsa, Tosawat Seetawan, Pennapa Muthitamongkol, Chanchana Thanachayanont
• Keywords: Na_0.5CoO₂, Solid-State Reaction, Thermoelectric Properties

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