Electrodeposition and characterization of poly-aniline-Bi-Te-Se-Sb thin films with thermoelectric properties

Polyaniline-Bi-Sb-Te-Se thin films have been prepared by electrodeposition and electrochemical reaction method in different potentials and different concentrations of PANI: (Bi (NO3)3·5H2O), H2SeO3, K2TeO3 and Sb2O3 on Al substrate from nitric acid solution at room temperature. The structure and morphology of thin films were investigated by Fourier-transform infrared (FTIR), X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM), and energy dispersive X-ray analysis (EDS) instruments. In addition, the thermoelectric power, resistivity, maximum power, and electrical conductivity of the thin films were evaluated. The results showed that an overall increase in voltage resulted in decreasing in the grain size and increasing in the dopant concentration. Furthermore, the coating morphology changed as the polyaniline precipitated, and nanoparticles were more uniformly distributed in the polymer coating via the increase in the voltage. Observations showed that the thin films were n-type semiconductors. Also, results showed that thermoelectric power increased by applied potential and temperature. It has been found that the chemical composition had a particular influence on the thermoelectric properties, which in comparison with previous works, at a similar temperature, a slight change in the chemical compound improved the thermoelectric properties by ∼ 65 percent.