Three-dimensional nanoporous Fe?O?/Fe?C-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 ?Ah cm(-2) ?m(-1) (3560 mAh cm(-3) or ?1118 mAh g(-1)) obtained at a discharge current density of 50 ?A cm(-2) (?0.17 C) with 88% retention after 100 cycles and 165 ?Ah cm(-2) ?m(-1) (1650 mAh cm(-3) or ?518 mAh g(-1)) obtained at a discharge current density of 1000 ?A cm(-2) (?6.6 C) for 1000 cycles were achieved. Meanwhile an energy density of 294 ?Wh cm(-2) ?m(-1) (2.94 Wh cm(-3) or ?924 Wh kg(-1)) and power density of 584 ?W cm(-2) ?m(-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.

SUBMITTER: Yang Y 

PROVIDER: S-EPMC4004288 | biostudies-other | 2014 Apr

REPOSITORIES: biostudies-other