Bismuth, tellurium, and bismuth telluride nanowires

Abstract

Decomposition of the precursor Bi[N(SiMe₃)₂]₃ in the presence of poly(1-hexadecene)_0.67-co-(1-vinylpyrrolidinone)_0.33 and a small amount of NaN(SiMe₃)₂ in 1,3-diisopropylbenzene solution at 203 °C gives Bi nanowires. The single-crystalline wires are several micrometers in length, and possess a mean diameter of 5.9 ± 2.4 nm. Decomposition of TeCl₄ in the presence of TOPO in polydecene solution at 250–300 °C gives Te nanowires. These nanowires are also single crystals exhibiting micrometer lengths. The Te nanowire mean diameters are in the range of 30–60 nm, and depend upon the reaction conditions employed. Attempts to grow Bi₂Te₃ nanowires from reactions of Bi- and Te-containing molecular precursors produce other Bi₂Te₃ crystallite morphologies. Efforts to convert Bi nanowires into Bi₂Te₃ nanowires are also unsuccessful. However, reactions of Te nanowires and BiPh₃ in polydecene solution at 160 °C do afford continuous Bi₂Te₃ nanowires, having micrometer lengths and mean diameters larger than those of the precursor Te nanowires. The Bi₂Te₃ nanowires are found to be encased in amorphous sheath structures, which apparently enforce the one-dimensional wire morphologies.