Green synthesis of Bi2Se3 hierarchical nanostructure and its electrochemical properties

Abstract

Bi₂Se₃ stacking nanosheets composed of several thin nanosheets have been successfully fabricated through a “green” method in the presence of ethylene glycol (EG) solution and applying sodium carboxymethyl cellulose (CMC) as a surfactant. The microstructure and morphology of the obtained product were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and selected-area electron diffraction (SAED) techniques. Effects of the concentration of KOH and CMC amount on the morphology of the as-prepared samples were investigated. Based on time-resolved experiments and FESEM observations, a self-assembling-fusing process was proposed to explain the formation of the Bi₂Se₃ stacking nanosheets. Furthermore, the electrochemical measurements indicate that the initial discharge capacities (715 mA h g⁻¹) of the Bi₂Se₃ stacking nanosheets were higher than the single Bi₂Se₃ nanosheets (421 mA h g⁻¹), which sheds light on a new way to improve the lithium storage properties of the Bi₂Se₃.