Porous NiCo2O4 nanostructures for high performance supercapacitors via a microemulsion technique

• Published in: Nano energy 2014-11, Vol.10, p.125-134
• Main Authors: An, Cuihua, Wang, Yijing, Huang, Yanan, Xu, Yanan, Jiao, Lifang, Yuan, Huatang
• Format: Article
• Language: English
• Subjects: Applied sciences; Capacitors. Resistors. Filters; Cross-disciplinary physics: materials science; rheology; Electrical engineering. Electrical power engineering; Energy; Energy storage; Energy. Thermal use of fuels; Exact sciences and technology; Materials; Materials science; Microemulsion technique; Nanoscale materials and structures: fabrication and characterization; Nanowires; Nickel cobaltite; Physics; Quantum wires; Supercapacitors; Transport and storage of energy; Various equipment and components
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2014.09.015

In this paper, porous Ni-substituted Co3O4 (ternary NiCo2O4) nanowires are synthesized via a simple microemulsion technique combined with a post thermal treatment. The as-prepared NiCo2O4 exhibits porous one-dimensional (1D) nanostructure, which preserves the morphology of the precursor. Moreover, the NiCo2O4 nanowires possess large surface area (53.6m2g−1), pore volume (0.241cm3g−1) and pore size (16.5nm). The porous 1D nanostructures and large surface area have huge benefits for practical applications in supercapacitors. Due to the well-aligned 1D nanowire microstructure and a higher electrical conductivity, these ternary NiCo2O4 electrodes possess high specific capacities of 1197Fg−1 at 1Ag−1 and capacitance retentions of 625Fg−1 at 8Ag−1. After 2000 cycles, the NiCo2O4 electrode can maintain 91.4% of its highest value, which demonstrates its superior cyclic stability performance. Also, the NiCo2O4 electrode exhibits high capacity retention when fast charging. These results show that the porous NiCo2O4 nanowires may be a promising electrode material for high performance electrochemical capacitors. 1D porous NiCo2O4 nanowires with excellent electrochemical performance have been successfully synthesized via a simple microemulsion technique. [Display omitted] •Porous NiCo2O4 nanowires were prepared via a simple microemulsion method.•The obtained NiCo2O4 nanowires are assembled by numerous nanoparticles.•The electrode possesses a high specific capacitance and good cycling performance.