Characterization of Bi₂Se₃ films prepared by electrodeposition and heat treatment

ABSTRACT

Bi₂Se₃ as a semiconductor with narrow band gap about 0.24 eV has good thermoelectric properties. Bi₂Se₃ thermoelectric films were prepared by electrodeposition using Bi₂O₃ and SeO₂ as raw materials, and the appropriate heat treatment process was adopted to improve the crystallinity of product films. The phases of product films were analyzed by X-ray diffraction (XRD) and the morphology was characterized by scanning electron microscopy (SEM), and the compositions of product films were analyzed by energy dispersive spectroscopy (EDS). The results show that the crystallinity of Bi₂Se₃ films can be improved significantly when heat treated at 350°C for 2 h or 400°C for 1 h. The XRD diffraction peaks are corresponding to (015), (1 0 10) and (110) crystal planes respectively. The surface of the product films shows particle aggregation, dendritic crystal and a few holes distributing irregularly.

KEYWORDS:

• Bi₂Se₃
• electrodeposition
• heat treatment
• thermoelectric material film

Funding

This work was financially supported by the National Natural Science Foundation of China (No.51272140).