Graphene Oxide/Iron Oxide Nanocomposites for Water Remediation

Graphene oxide/iron (III-VI) oxides nano composites have been produced with a fast and one-pot synthesis. K2FeO4 (Fe(VI)-based compound), obtained from a dry synthesis, has been used as a green oxidant of graphite to produce graphene oxide, avoiding the use of the toxic permanganates. Graphene oxide flakes with a low oxidation degree and decorated with iron oxide have been obtained in one-step reaction. The material has been characterized by several techniques to investigate the structure (SEM, TEM analysis), the composition (X-ray fluorescence, XPS, FTIR, UV-visible, fluorescence, and Raman spectroscopy) and the performance (HPLC). The combined use of ferrate and graphene oxide/iron oxide is an efficient, cheap, and green alternative for water remediation. Real water samples containing different types of emerging pollutants (organic dyes, pesticides, and pharmaceutical drugs) have been efficiently decontaminated obtaining an abatement of 99% in a few minutes. The nanocomposite is paramagnetic and can be easily removed from water with a magnet after depollution. The materials have shown one of the best decontamination performance reported in the scientific literature so far.