Synthesis, structural characterisation and thermoelectric properties of Bi sub(1-x)Pb sub(x)OCuSe

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2013-09, Vol.1 (39), p.12270-12275
• Main Authors: Luu, Son DN, Vaqueiro, Paz
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c3ta12753b

The effect of Pb super(2+) doping on the structure and thermoelectric properties of BiOCuSe (also known as BiCuSeO or BiCuOSe) is described. With increasing Pb super(2+) content, the expansion of the unit cell results in a weakening of the bonding between the [Bi sub(2(1-x))Pb sub(2x)O sub(2)] super(2(1-x)+) and the [Cu sub(2)Se sub(2)] super( 2(1-x)-) layers. The electrical resistivity and Seebeck coefficient decrease in a systematic way with growing Pb super(2+) levels. The thermal conductivity rises due to the increase of the electronic contribution with doping. The power factor of materials with a 4-5% Pb super(2+) content takes values of ca. 8 mu W cm super(-1) K super(-2) over a wide temperature range. ZT at 673 K is enhanced by ca. 50% when compared to values found for other dopants, such as Sr super(2+) or Mg super(2+).