Hierarchical Bi2Se3 microrods: microwave-assisted synthesis, growth mechanism and their related properties

Bi2Se3 microrods composed of nanoparticles have been successfully fabricated through a self-sacrificial template microwave-assisted method in the presence of a ethylene glycol (EG) solution, applying ascorbic acid (AA) as a reducing agent and soluble starch (SS) as a surfactant. The structure and morphology of the obtained products 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. Based on the time-dependent experiments, a possible formation mechanism was proposed. The electrical transport properties were investigated by measuring the electrical conductivity and the Seebeck coefficient at a temperature range of 298 to 523 K and the maximum power factor can be as high as 92 μW m−1 K−2 at 523 K. The intercalation behavior of Li ions into the obtained Bi2Se3 microrods was also investigated. The discharge capacity of the sample at room temperature can reach up to 870 mA h g−1, indicating potential applications in electrochemical lithium intercalation and high-energy batteries.