title: High-intensity ultrasonication as a way to prepare graphene/amorphous iron oxyhydroxide hybrid electrode with high capacity in lithium battery.
abstract: The preparation of graphene/iron oxyhydroxide hybrid electrode material with very homogeneous distribution and close contact of graphene and amorphous iron oxyhydroxide nanoparticles has been achieved by using high-intensity ultrasonication. Due to the negative charge of the graphene surface, iron ions are attracted toward the surface of dispersed graphene, according to the zeta potential measurements. The anchoring of the FeO(OH) particles to the graphene layers has been revealed by using mainly TEM, XPS and EPR. TEM observations show that the size of the iron oxide particles is about 4 nm. The ultrasonication treatment is the key parameter to achieve small particle size in these graphene/iron oxyhydroxide hybrid materials. The electrochemical behavior of composite graphene/amorphous iron oxyhydroxide prepared by using high-intensity ultrasonication is outstanding in terms of gravimetric capacity and cycling stability, particularly when metallic foam is used as both the substrate and current collector. The XRD-amorphous character of iron oxyhydroxide in the hybrid electrode material and the small particle size contribute to achieve the improved electrochemical performance.
authors.affiliation: Universidad de Córdoba, Campus de Rabanales, Edificio C3, Laboratorio de Química Inorgánica, 14071 Córdoba, Spain.
authors.forename: José R
authors.initials: JR
authors.lastname: González
authors.affiliation: Instituto Nacional del Carbón (INCAR-CSIC), Apdo. 73, 33080 Oviedo, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Menéndez
authors.affiliation: Universidad de Córdoba, Campus de Rabanales, Edificio C3, Laboratorio de Química Inorgánica, 14071 Córdoba, Spain. Electronic address: iq2alror@uco.es.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Alcántara
authors.affiliation: Universidad de Córdoba, Campus de Rabanales, Edificio C3, Laboratorio de Química Inorgánica, 14071 Córdoba, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Nacimiento
authors.affiliation: Universidad de Córdoba, Campus de Rabanales, Edificio C3, Laboratorio de Química Inorgánica, 14071 Córdoba, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Tirado
authors.affiliation: Institute of General and Inorganic Chemistry, Bulgarian Academy of Science, 1113 Sofia, Bulgaria.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Zhecheva
authors.affiliation: Institute of General and Inorganic Chemistry, Bulgarian Academy of Science, 1113 Sofia, Bulgaria.
authors.forename: Radostina
authors.initials: R
authors.lastname: Stoyanova
keywords: Composite; Electron paramagnetic resonance; Graphene; Lithium batteries; Mössbauer spectroscopy