Thermoelectric power factor optimization in hydrothermally synthesized SnO2 nanoparticles by Cu doping

Abstract

This paper investigates the effect of copper (Cu) doping on the thermoelectric properties of Tin Oxide (SnO2) nanoparticles. The Cu doped samples were prepared with the help of hydrothermal method using different concentration of Cu atoms. Various characterization techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Hall effect and Seebeck measurements are performed to analyze the structural, morphological, electrical and thermoelectric of grown nanomaterials. Based upon the XRD and Raman measurements, it was concluded that the crystal quality of SnO2 samples degraded with increasing the doping concentration of Cu atoms. SEM images reveal that with the increase of Cu concentration, the porosity of the samples decreases, and the distribution of nanoparticle sizes becomes more uniform. The electrical conductivity of the Cu-doped SnO2 nanoparticles increases with increasing the Cu concentration because Cu atoms are supposed to act as donor defects in SnO2 crystal. However, the Seebeck coefficient decreases, indicating a reduced ability to generate a thermoelectric voltage in response to a temperature gradient. The power factor, initially increases with Cu doping, however, beyond an optimal value, the power factor starts to decrease, indicating a saturation or detrimental effect caused by excessive Cu doping.

Keywords

• SnO2 nanoparticles
• Cu doping
• Thermoelectric performance
• XRD