L-cystine-Assisted Growth and Mechanism of CuInS₂ Nanocrystallines via Solvothermal Process

L-cystine is successfully used as a kind of sulfur source to grow CuInS₂ nanocrystallines at 200°C for 18 h in a mixed solution made of 20 mL ethylenediamine and 20 mL distilled water. The diameter of the CuInS₂ nanocrystallines ranges from 300 to 500 nm. The structure of nanocrystallines is determined to be of the tetragonal phase of CuInS₂. A reasonable possible mechanism for the growth of CuInS₂ nanocrystallines is proposed. The as−obtained CuInS₂ products are examined using diverse techniques including x-ray powder diffraction, x-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, selected-area electron diffraction and high-resolution transmission electron microscopy.