Three-dimensional reduced graphene oxide decorated with iron oxide nanoparticles as efficient active material for high performance capacitive deionization electrodes

A three-dimensional reduced graphene oxide decorated with iron oxide nanoparticles (3D rGO-Fe2O3) material with a suitable porous structure was synthesised using a one-step hydrothermal process in order to fabricate novel electrodes for capacitive deionization (CDI) water desalination. The morphological and structural properties of the as-synthesised compounds were characterised by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Raman spectroscopy (RS), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The CDI electrodes were electrochemically analysed by cyclic voltammetry (CV) and electrochemical impedance spec-troscopy (EIS). A maximum value of specific capacitance of 345 F g- 1 was achieved at 5 mV s- 1 scan rate using a NaCl 0.1 mol L - 1 solution. The ion removal performance of the CDI electrodes was evaluated with NaCl so-lutions of different concentrations, showing electrosorption capacities as high as 945 mg g- 1 for 11,700 mg L - 1 (200 mmol L - 1) NaCl solutions, which substantially surpasses results of other carbon-based CDI electrodes.