Synthesis and characterization of graphene oxide, tin oxide, and reduced graphene oxide-tin oxide nanocomposites

Abstract

The present study reports the synthesis and characterization of graphene oxide (GO), tin oxide nanostructures, and reduced GO (rGO)-tin oxide nanocomposites. The modified Hummer's method was used for the synthesis of GO. Tin oxide nanoparticles were synthesized by co-precipitation method using SnCl2 as tin source. The rGO-tin oxide nanocomposites were synthesized by hydrothermal method using GO and SnCl2 as tin source. The synthesized nanostructures were characterized using powder XRD, FESEM, EDX spectroscopy, TEM, SAED, FTIR spectroscopy, UV–visible spectroscopy, Raman spectroscopy, and TGA. The XRD pattern of the graphite powder shows intense (002) plane peak at 2θ = 26.78° along with the other graphitic XRD peaks. In addition, XRD peaks at 2θ ∼ 14°, 16.8°, 21.18°, and 24.18° were also observed. The characteristic GO (001) plane peak in the XRD pattern could be not be observed in the oxidative exfoliation GO. The Raman spectrum of the graphite powder shows intense crystalline G band, low-intensity defect related D, multi-layered graphitic flake related 2D-band with intensity ratio ID/IG=0.08 and I2D/IG=0.46. The oxidative exfoliated GO shows the degradation of the graphite XRD peaks, but the characteristic GO (001) plane XRD peak could not be observed. The TEM image shows the formation of GO sheets on the oxidative exfoliation of graphite. The d-spacing obtained from the observed hexagonal SAED pattern of the oxidative exfoliated GO was found to be much lower than graphite d-spacing. Raman, UV–visible, FTIR, and TGA studies indicate the formation of GO under oxidative exfoliation of graphite under Hummer’s method. The band gap values of around 1.70 eV from the UV–visible optical absorption also indicates the formation of graphene in the oxidative exfoliated GO. The observed results indicate the formation of graphene embedded amorphous GO.