ICT2014 Abstracts

Traditionally the top down approach to obtain nanoscale grain size in thermoelectric materials has been used, however this approach offers few opportunities to truly control the nano-scale grain size, particle shape, or fine composition/structural properties, which are all required for developing the next generation of highly efficient thermoelectric materials. In contrast, in this study a bottom up synthetic approach is used which offers many advantages such as direct control over nanoparticle size and shape or tailoring of the particle composition and structure towards thermoelectrics that more directly harness the beneficial characteristics of nanoparticles. Chalcopyrite (CuFeS₂) nanoparticles were developed using a bottom-up wet chemical technique with tunable composition that can be manipulated simply by control over the metallic feeding ratio. The resulting nanoparticles are fully characterized using techniques such as TEM, XRD, XPS, HAADF-STEM and others to map their physical and chemical properties. The results will be discussed in terms of the synthetic approach, characterization of the materials and the implications to the thermoelectric properties for low temperature applications. This chalcogenide material system is notable for being highly sustainable from the standpoint of elemental abundance and non-toxic nature, making the work an important fundamental study on nanoparticle based thermoelectrics.