• 文献标题:   Plasma-grown graphene petals templating Ni-Co-Mn hydroxide nanoneedles for high-rate and long-cycle-life pseudocapacitive electrodes
  • 文献类型:   Article
  • 作  者:   XIONG GP, HE PG, LIU L, CHEN TF, FISHER TS
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF MATERIALS CHEMISTRY A
  • ISSN:   2050-7488 EI 2050-7496
  • 通讯作者地址:   Purdue Univ
  • 被引频次:   51
  • DOI:   10.1039/c5ta05441a
  • 出版年:   2015

▎ 摘  要

Ni-Co-Mn triple hydroxide (NCMTH) nanoneedles were coated on plasma-grown graphitic petals (GPs) by a facile one-step hydrothermal method for high-rate and long-cycle-life pseudocapacitive electrodes. Structural and compositional characteristics of NCMTHs indicate that the multi-component metal elements distribute homogeneously within the NCMTHs. Comparison of the electrochemical performance of the three-dimensional NCMTH electrodes to Ni-Co double hydroxides reveals that a synergistic effect of the hierarchical structure of GPs and NCMTHs enables their high rate capability and long cycle life. The NCMTH electrode maintains over 95% of its capacitance at a high charge/discharge rate of 100 mA cm(-2) relative to its low-current (1 mA cm(-2)) capacitance; and it exhibits very high specific capacitance of approximately 1400 F g(-1) (based on the mass of NCMTH), high specific energy density (z30 W h kg(-1)) and power density (z39 kW kg(-1)) at a high current density of 100 mA cm(-2), and excellent long-term cyclic stability (full capacitance retention over 3000 cycles). To assess functional behavior, two-terminal asymmetric supercapacitor devices with NCMTHs on graphitic petals as positive electrodes were assembled and tested to reveal ultrafast charge/discharge rates up to 5000 mV s(-1) (approx. two orders of magnitude faster than conventional asymmetric devices based on metal hydroxides) with high rate capabilities, and excellent long-term cyclic stability (full capacitance retention over 10 000 cycles).