Production of Bi2O3 nanorods via a catalyst-free approach

We fabricated β-Bi2O3 nanorods on silicon substrates without using a metal catalyst. Trimethylbismuth and O2 were used as the bismuth and the oxygen sources, respectively, in the metalorganic chemical-vapor deposition process. The samples were characterized using scanning electron microscopy, X-ray diffractometry, and transmission electron microscopy. With the O2/Ar gas flow ratio affecting the sample morphology, we obtained thinner 1D nanorods with a tetragonal β-Bi2O3 structure at a smaller ratio. We proposed a vapor-solid process as the growth mechanism for the β-B/E nanorods. The photoluminescence measurements of the Bi2O3 nanorods at room temperature exhibited an emission band peaked at around 425 - 440 nm.