Facile synthesis of α-Fe2O3@graphene oxide nanocomposites for enhanced gas-sensing performance to ethanol

A simple and eco-friendly approach was used to prepare α-Fe2O3@graphene oxide (α-Fe2O3@GO) nanocomposites with different iron oxide content in lower temperature. The nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and nitrogen adsorption–desorption techniques. The results show that α-Fe2O3 nanoparticles with particle sizes of 60–100 nm are uniformly anchored on the surface of GO nanosheets at lower hydrothermal reaction. The specific surface area of α-Fe2O3@GO (114.57 m2/g) was about threefold larger than that of pure iron oxide (33.37 m2/g). Moreover, α-Fe2O3@GO nanocomposites with optimal mass ratio (8:1) between iron oxide and GO, which exhibited enhanced response to 100 ppm ethanol (14.82) in comparison with pure α-Fe2O3 (3.48) at 260 °C. The improved sensitive performance is in contact with larger surface area and incremental active sites in interface owing to introducing GO. The results reveal that GO is crucial to improve gas sensing performance.