title: Iron oxide-decorated carbon for supercapacitor anodes with ultrahigh energy density and outstanding cycling stability.
abstract: Supercapacitor with ultrahigh energy density (e.g., comparable with those of rechargeable batteries) and long cycling ability (>50000 cycles) is attractive for the next-generation energy storage devices. The energy density of carbonaceous material electrodes can be effectively improved by combining with certain metal oxides/hydroxides, but many at the expenses of power density and long-time cycling stability. To achieve an optimized overall electrochemical performance, rationally designed electrode structures with proper control in metal oxide/carbon are highly desirable. Here we have successfully realized an ultrahigh-energy and long-life supercapacitor anode by developing a hierarchical graphite foam-carbon nanotube framework and coating the surface with a thin layer of iron oxide (GF-CNT@Fe2O3). The full cell of anode based on this structure gives rise to a high energy of ∼74.7 Wh/kg at a power of ∼1400 W/kg, and ∼95.4% of the capacitance can be retained after 50000 cycles of charge-discharge. These performance features are superior among those reported for metal oxide based supercapacitors, making it a promising candidate for the next generation of high-performance electrochemical energy storage.
authors: †Department of Materials Science and Engineering, National University of Singapore, 117574 Singapore.
authors: Cao
authors: C
authors: Guan
authors: ‡School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore.
authors: Jilei
authors: J
authors: Liu
authors: §School of Engineering, Nanyang Polytechnic, 569830 Singapore.
authors: Yadong
authors: Y
authors: Wang
authors: †Department of Materials Science and Engineering, National University of Singapore, 117574 Singapore.
authors: Lu
authors: L
authors: Mao
authors: ⊥School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
authors: Zhanxi
authors: Z
authors: Fan
authors: ‡School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore.
authors: Zexiang
authors: Z
authors: Shen
authors: ⊥School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
authors: Hua
authors: H
authors: Zhang
authors: †Department of Materials Science and Engineering, National University of Singapore, 117574 Singapore.
authors: John
authors: J
authors: Wang
keywords: atomic layer deposition; cycling stability; energy density; metal oxide; supercapacitor anode