Large-Scale Synthesis, Growth Mechanism, and Photoluminescence of Ultrathin Te Nanowires Guangcheng Xi, Yankuan Liu, Xiaoqing Wang, Xiaoyan Liu, Yiya Peng, and Yitai Qian* Hefei National Laboratory for Physical Science at Microscale and Department of Chemistry, UniVersity of Science & Technology of China, Hefei, Anhui 230026, P.R. China
CRYSTAL GROWTH & DESIGN 2006 VOL. 6, NO. 11 2567-2570
ReceiVed June 1, 2006; ReVised Manuscript ReceiVed August 17, 2006
ABSTRACT: In this paper, a green chemical synthetic route was developed to synthesize single-crystalline Te nanowires with an average diameter of 7 nm at a low temperature (90 °C) by using ascorbic acid as a reducing agent, Na2TeO3 as a tellurium source, and surfactant cetyltrimethylammonium bromide (CTAB) as a structure-directing agent. The morphology of Te nanowires in the presence of CTAB is strongly dependent on the reaction conditions such as the concentration of CTAB, reaction time, and reducing agents. A surfactant-assisted solid-solution-solid growth mechanism was identified to explain the formation of ultrathin Te nanowires. The single-crystalline Te nanowires with an average diameter of 7 nm display strong luminescence emission in the blue-violet region. 1. Introduction Tellurium (Te) is a narrow band gap semiconductor (∼0.35 eV) that displays interesting physical properties, including nonlinear optical responses, photoconductivity, and thermoelectric properties.1,2 The properties make it useful as an infrared photoconductive detector, piezoelectronic devices, and thermoelectronic material.3-5 Recently, these useful properties have stimulated the search for new synthetic methodologies for wellcontrolled Te nanostructures. Several reports on high-temperature physical or chemical Te syntheses have recently been published.6-11 Compared with high-temperature physical synthetic methods, the chemical methods appear to be of particular interest, because they offer the potential of facile scale-up and occur at moderate temperatures (
