Electrochemical fabrication of ordered Bi2S3 nanowire arrays

We have successfully fabricated ordered, well-crystallized Bi2S3 nanowire arrays embedded in the nanochannels of porous anodic aluminum oxide templates by direct current electrodeposition from a dimethylsulfoxide solution containing BiCl3 and elemental sulfur. X-ray diffraction and selected area electron diffraction investigations demonstrate that the Bi2S3 nanowires have an orthorhombic uniform structure. Electromicroscopy results show that the nanowires are quite ordered with diameters of about 40 nm and lengths up to 5 microns. X-ray energy dispersion analysis indicates that the atomic composition of Bi and S is very close to a 2 : 3 stoichiometry. The optical properties of these nanowires were characterized by optical absorption techniques. These studies reveal that the annealed Bi2S3 nanowires have an optical band edge (direct) of about 1.56 eV. (Author)