Characterization of Bi2Se3 prepared by electrodeposition

Abstract

Bi2Se3 compound was deposited catholically under potential control, from a mixture solution composed from equimolar SeO2 and BiCl3. The concentration of selenium and bismuth precursors was about 5 ∙ 10−3 M. The electrodeposited films were grown on FTO substrates (Transparent Conductive Glass Fluorine-Doped Tin Oxide (FTO)–Coated Glass). Deposition potential was determined from cyclic voltammetry (CV) where the platinum mesh was taken as working electrode. The growth kinetics depends on the applied potential. It was found, using EDS technique, that suitable ratio of Se/Bi corresponding to Bi2Se3 was reached at − 250 mV vs. SCE (saturated calomel electrode). X-ray and grazing X-ray diffraction revealed that the obtained film at − 250 and − 200 mV/SCE consisted a rhombohedral Bi2Se3 structure. Raman shift was employed to corroborate the X-ray results with the possibility of formation of a rhombohedral Bi2Se3 when the applied potential was − 200 mV (vs. SCE). The Bi2Se3-obtained films were an n-type semiconductor with a carrier charge concentration which depends on the applied potential.