Adsorption/Reduction of NO2 on Graphite Oxide/Iron Composites

Adsorption of NO2 and the retention of NO (the product of NO2 reduction by carbon) on the materials prepared from iron acetato complex and its Mixture with graphite oxide were studied. The surface of the materials was characterized using adsorption of nitrogen, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and thermogravimetric analysis (TGA). The results showed that the development of texture and porosity along with formation of some active surface species on the graphite oxide/iron composite materials leads to an increase in NO2 adsorption. An immediate reduction of NO2 to NO by carbon was noticed for all samples except for the one that contained a smallest amount of carbon in a mostly oxidized form. The retention of NO on the surface of the materials does not depend on their structural characteristics. Better performance is found for the materials that contain active iron species, such as gamma-FeOOH and alpha-Fe2O3, which likely react with NO molecules forming surface nitrates.