Synthesis, characterization and sensing properties of mesoporous C/SnO2 nanocomposite

Mesoporous C/SnO2 nanocomposites have been successfully prepared by hydrothermal treatment of aqueous dispersion of fullerene C60 in the presence of Sn salts and following an annealing process. The C/SnO2 nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption -desorption technique. Results demonstrated the C/SnO2 nanocomposites were mesoporous structures with average pore size about 10 nm. The composites were composed of nanocrystal SnO2 with diameters at the range of 7-10 nm and carbon crystallite on SnO2 grain boundary. When being used as gas sensing material, the nanostructure C/SnO2 exhibited very sensitive to n-butanol, n-propanol, ethanol and formaldehyde at low operating temperature around 100 degrees C. Meanwhile, the sensors presented favorable linearity, good selectivity and stability. It was found that carbon crystallite on Sn02 grain boundary could improve the sensitivity and selectivity of SnO2 material, as well as reduce the sensing temperatures and the response time. The enhancement of the sensing response was mainly attributed to the catalytic effect and electron donor of carbon crystallite. (C) 2016 Elsevier B.V. All rights reserved.