Ce-doped Bi<sub>2</sub>O<sub>3</sub> nanorods and thermoelectric properties

Abstract

Nowadays, the problem of environmental pollution and energy shortage caused by the burning of a large number of fossil fuels (coal, oil and gas) is becoming more and more serious. Finding an efficient, green, low-cost and sustainable energy material is the focus of energy science research now. Thermoelectric technology is able to generate a temperature gradient by collecting waste heat from factories, cars and so on and converts it into electricity through the Seebeck effect, and through the Peltier effect, it can be used for refrigeration. Thermoelectric material is the key to the thermoelectric technology. Therefore, the performance research of thermoelectric materials will play an important role in solving energy problems in the future. As a green environmental material, Bi2O3 possesses a low cost and high Seebeck coefficient of thermoelectric materials. Due to poor electrical conductivity; however, the power factor (PF) of Bi2O3 has so far been less than 1.05×10−3 W K−2 m. It is one of the most important way to improve the efficiency of thermoelectric conversion to obtain counterpart nanomaterials. In this paper, through a simple chemical vapor deposition (CVD), Ce x Bi2− x O3 ( x =0%, 0.1%, 0.2%, 0.3%) nanorods were successfully fabricated. As for the chemical composition, morphology, and microstructure analysis, conventional X-ray diffraction (XRD) pattern/small grazing incident X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS) were used to prove to be the Ce x Bi2− x O3 sample. Through scanning/transmission electron microscope, it was found that products were dispersed uniformly nanorods, and counterpart samples cold be pressed into a round piece. Based on Seebeck coefficient/electrical resistivity measurement system using thermoelectric performance testing system (ZEM-3), electrical transport properties of the samples were characterized. Laser thermal conductivity meter (LASER FLASH DLF-1) and EXSTAR differential scanning calorimeter (6200) were used to test the thermal conductivity of the sample. The obtained results showed that the power factor (PF) and ZT value of the sample (Ce0.2Bi1.8O3) arrived at 1.265×10−2 W K−2 m−1 and 0.57×10−2 at 479 K, respectively, which is far higher than that of the un-doped samples. So Ce-doped Bi2O3 thermoelectric nanomaterials have a good application prospect for energy, material and devices.