Nano-inclusions: a novel approach to tune the thermal conductivity of In sub(2)O sub(3)

• Published in: Physical chemistry chemical physics : PCCP Vol. 15; no. 40; pp. 17595 - 17600
• Main Authors: Xu, Wei, Liu, Yong, Chen, Bo, Liu, Da-Bo, Lin, Yuan-Hua, Marcelli, Augusto
• Format: Journal Article
• Language: English
• Published: 01.09.2013
• Subjects: Heat transfer; Indium oxides; Nanostructure; Scanning electron microscopy; Scattering; Thermal conductivity; Thermoelectricity; Zinc oxide
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c3cp52942h

Indium oxides such as In sub(2)O sub(3) based thermoelectric ceramics exhibit a figure of merit ZT similar to 0.5 above 1000 K, while optimized ZnO based thermoelectrics may reach ZT similar to 0.3 at 1273 K. A way to further optimize the thermoelectric performance is to tune the thermal conductivity. In this work, a reduction of the thermal conductivity greater than 30% has been observed. Combining thermal conductivity measurements, Scanning Electron Microscopy (SEM) images, X-ray Absorption Fine-structure spectroscopy (XAFS) data and Full Multiple Scattering calculations, we associated the phenomenon with an effective scattering of mid- and long-wavelength phonons by embedded ZnO nano-inclusions in the In sub(2)O sub(3) matrix. The results suggest a protocol for the synthesis of new heat-designed materials for many novel applications, such as high ZT thermoelectrics, thermal crystals, heat optics devices, etc.