Synthesis and Electrical Characterization of Tin Oxide Nanostructures
- PDF / 725,064 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 18 Downloads / 207 Views
1178-AA06-33
Synthesis and Electrical Characterization of Tin Oxide Nanostructures Olivia M. Berengue*1, Cleocir J. Dalmaschio2, Tiago G. Conti2, Adenilson J. Chiquito1, Edson R. Leite2 1 Nanolab, Department of Physics, Federal University of São Carlos, C. Postal 13560-905 - São Carlos, SP, Brazil. 2 LIEC, Department of Chemistry, Federal University of São Carlos, C. Postal 676, 13565-905 São Carlos, SP, Brazil. ABSTRACT
Sn3O4 nanobelts were grown by a carbothermal evaporation process of SnO2 powders in association with the well known vapour-solid mechanism (VS). The nanobelts crystal structure was investigated by x-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), raman spectroscopy and field emission gun scanning electron microscopy (FEGSEM). The structural and morphological characterization has confirmed the growth of single crystal nanobelts. The electrical characterization (current-voltage, temperature-dependent resistance curves) of individual Sn3O4 nanobelts was performed at different temperatures and light excitation. The experiments revealed a semiconductor – like character as evidenced by the resistance decreasing at high temperatures. The transport mechanism was identified as the variable range hopping. INTRODUCTION
Since the discovery of the nanoworld the promise of faster, cheaper and smaller electronic devices has become close to be reality. The design of these new nanodevices depends on the understanding of the fundamental structural and electronic characteristics as well as the growth mechanisms of their building blocks. In this sense semiconductor nanowires, nanotubes and quantum dots has been extensively studied because of their characteristic features for application in devices and in nanoelectronics. Moreover, as low dimensional structures they are also interesting from the point of view of fundamental physics because they are structures where the quantum mechanical effects cannot be neglected [1]. The oxide-based nanostructures deserve significant attention because of their unique combination of interesting structural, optical and electronic properties. In this context, this paper reports the synthesis, structural and electrical characterization of Sn3O4 nanobelts. The x-ray diffraction, high resolution transmission electron microscopy and Raman spectroscopy measurements allow confirming the samples triclinic structure and their single crystalline character. The field emission gun scanning electron microscopy evidenced the belt-like structure and confirms the VS growth of the samples. Photocurrent measurements show that the samples present an energy gap of 2.96 eV characterizing a wide band gap material. The temperaturedependent resistance data (using ultraviolet, illumination) provided information about the
nanobelts transport mechanism. An insulator-like behavior was found in dark conditions. By using ultraviolet (UV) illumination it was then clear that samples are behaving like semiconductor crystals: the strongest evidence of the semiconducting behavior wa
Data Loading...
