title: Three-dimensional nanoporous Fe₂O₃/Fe₃C-graphene heterogeneous thin films for lithium-ion batteries.
abstract: Three-dimensional self-organized nanoporous thin films integrated into a heterogeneous Fe2O3/Fe3C-graphene structure were fabricated using chemical vapor deposition. Few-layer graphene coated on the nanoporous thin film was used as a conductive passivation layer, and Fe3C was introduced to improve capacity retention and stability of the nanoporous layer. A possible interfacial lithium storage effect was anticipated to provide additional charge storage in the electrode. These nanoporous layers, when used as an anode in lithium-ion batteries, deliver greatly enhanced cyclability and rate capacity compared with pristine Fe2O3: a specific capacity of 356 μAh cm(-2) μm(-1) (3560 mAh cm(-3) or ∼1118 mAh g(-1)) obtained at a discharge current density of 50 μA cm(-2) (∼0.17 C) with 88% retention after 100 cycles and 165 μAh cm(-2) μm(-1) (1650 mAh cm(-3) or ∼518 mAh g(-1)) obtained at a discharge current density of 1000 μA cm(-2) (∼6.6 C) for 1000 cycles were achieved. Meanwhile an energy density of 294 μWh cm(-2) μm(-1) (2.94 Wh cm(-3) or ∼924 Wh kg(-1)) and power density of 584 μW cm(-2) μm(-1) (5.84 W cm(-3) or ∼1834 W kg(-1)) were also obtained, which may make these thin film anodes promising as a power supply for micro- or even nanosized portable electronic devices.
authors.affiliation: Department of Chemistry, ‡Smalley Institute for Nanoscale Science and Technology, and §Department of Materials Science and NanoEngineering, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiujun
authors.initials: X
authors.lastname: Fan
authors.forename: Gilberto
authors.initials: G
authors.lastname: Casillas
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Peng
authors.forename: Gedeng
authors.initials: G
authors.lastname: Ruan
authors.forename: Gunuk
authors.initials: G
authors.lastname: Wang
authors.forename: Miguel Jose
authors.initials: MJ
authors.lastname: Yacaman
authors.forename: James M
authors.initials: JM
authors.lastname: Tour
mesh_terms: D011211:Electric Power Supplies; D004563:Electrochemistry; D005290:Ferric Compounds / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D007700:Kinetics; D008094:Lithium / Q000737:chemistry*; D058608:Nanopores; D013696:Temperature
chemical_list: D005290:Ferric Compounds; D006108:Graphite; D008094:Lithium