Facile one-step synthesis of CdSxSe1- x nanobelts with uniform and controllable stoichiometry

Abstract

We present a simple yet effective one-step approach with a specially designed substrate holder to synthesize single crystalline ternary CdS xSe1-x nanobelts with uniform chemical stoichiometry and accurately controllable compositions (0 ≤ x ≤ 1). The micromorphologies and detailed structures of these nanobelts were studied by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, micro-Raman spectra, and energy-dispersive X-ray spectroscopy. The elements distribution was explored using elemental mapping. All the characteristic results indicate that the nanobelts exhibit high quality single crystalline wurtzite structure. Photoluminescence spectra obtained from these nanobelts show that the near-band-edge energy can be systematically modulated in the range of 1.73 to 2.44 eV. Functional electrical application of these nanobelts was achieved by a fabricated CdSxSe1-x nanonet-field effect transistor (FET). A lower threshold voltage and a much higher ON-OFF ratio than pure CdS- and CdSe-based FET were obtained. These nanonet-FETs also show potential as photosensors with rapid photoelectrical response to light illuminations. © 2011 American Chemical Society.