title: Pseudocapacitive Sodium Storage in Mesoporous Single-Crystal-like TiO2-Graphene Nanocomposite Enables High-Performance Sodium-Ion Capacitors.
abstract: Sodium-ion capacitors can potentially combine the virtues of high power capability of conventional electrochemical capacitors and high energy density of batteries. However, the lack of high-performance electrode materials has been the major challenge of sodium-based energy storage devices. In this work, we report a microwave-assisted synthesis of single-crystal-like anatase TiO2mesocages anchored on graphene as a sodium storage material. The architecture of the nanocomposite results in pseudocapacitive charge storage behavior with fast kinetics, high reversibility, and negligible degradation to the micro/nanostructure. The nanocomposite delivers a high capacity of 268 mAh g-1at 0.2 C, which remains 126 mAh g-1at 10 C for over 18 000 cycles. Coupling with a carbon-based cathode, a full cell of sodium-ion capacitor successfully demonstrates a high energy density of 64.2 Wh kg-1at 56.3 W kg-1and 25.8 Wh kg-1at 1357 W kg-1, as well as an ultralong lifespan of 10 000 cycles with over 90% of capacity retention.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Zaiyuan
authors.identifier: 0000-0002-9925-7513
authors.initials: Z
authors.lastname: Le
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Fang
authors.identifier: 0000-0003-0885-5604
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Ping
authors.initials: P
authors.lastname: Nie
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Xinru
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liu
authors.affiliation: Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Department of Chemistry, Shanghai Normal University , Shanghai, 200234, China.
authors.forename: Zhenfeng
authors.initials: Z
authors.lastname: Bian
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Gen
authors.identifier: 0000-0003-3504-3572
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Hao Bin
authors.identifier: 0000-0002-0725-6442
authors.initials: HB
authors.lastname: Wu
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Lu
keywords: TiO2; energy storage; nanocomposite; pseudocapacitive; sodium-ion capacitor