Hydrothermal Preparation of Fe2O3 Nanoparticles for Fe-Air Battery Anodes

Fe2O3 nanoparticles were synthesized from iron nitrate [Fe(NO3)3·9H2O] by hydrothermal method for Fe-air battery anodes. The crystal structure and morphology of the obtained Fe2O3 powder were studied by x-ray diffraction and scanning electron microscopy. Fe2O3/acetylene black (AB) composite electrodes were fabricated by mixing the synthesized Fe2O3 nanoparticles with AB carbon and were then subjected to electrochemical measurements. Results indicated that the duration of hydrothermal treatment significantly influences the morphology and size of synthesized Fe2O3. The morphology and particle size of Fe2O3 also affect the electrochemical properties of Fe2O3/AB composite electrodes, viz., smaller particles provide greater capacity than larger ones. The resistance of electrodes gradually increases during cycling, thereby causing a decrease in the capacity of Fe2O3/AB electrodes.