Asymmetric hybrid capacitor based on Co 3 O 4 nanowire electrode
- PDF / 2,003,292 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 24 Downloads / 243 Views
ORIGINAL PAPER
Asymmetric hybrid capacitor based on Co3O4 nanowire electrode Yue Zhao 1 & Henqi Liu 1 & Pengfei Hu 1 & Jianrong Song 1 & Li Xiao 1 Received: 16 May 2020 / Accepted: 10 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract In this work, Co3O4 nanowires grown on Ni foam have been synthesized through a facile hydrothermal approach, revealing large capacity of 310.4 C g−1 and superior cycling stability of 80.3% capacity retention after 6000 cycles. The asymmetric supercapacitors were fabricated based on Co3O4//AC device, which delivers an energy density of 0.4 mWh cm−3 at power density of 3.99 mW cm−3 and an excellent cycle life of 79.2% capacity retention after 10,000 cycles. Keywords Co3O4 nanowires . Electrochemical performance . Hybrid supercapacitors . Cycling stability
Introduction Recently, energy storage has obtained lots of focuses [1–6]. Lithium-ion batteries and supercapacitors have attracted worldwide attention because they play a vital role in our daily lives as the main power sources for portable electronics [7–9]. However, low power density and large size limit their further applications. Meanwhile, supercapacitors have attracted more and more attention as promising electrochemical energy storage devices due to their high power density, fast chargedischarge speed, and long cycle stability [10–12]. Usually, electrical double-layer capacitors store electrical energy as an electrostatic accumulation of the charges in the electric double layer near the interfaces; pseudocapacitors can take advantage of reversible faradaic reactions, which can offer much greater specific capacitance [13, 14]. The performance of supercapacitors is determined by the shapes and spatial structures of electrode materials [15, 16]. Therefore, rational design and fabrication of desiring electrode materials with large aspect ratio and more active sites are very significant. Among various electrode materials, Co3O4 with spinel structure has received enormous attention due to its low cost, higher theoretical capacitance, excellent electrochemical activity, and better electrical conductivity than corresponding single metal oxides and binary sulfides [16–20]. However,
* Li Xiao [email protected] 1
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, People’s Republic of China
some of them were synthesized either by two-step process [21–23] or using some surfactants [24]. Herein, we fabricate Co3O4 nanowires grown on nickel foam through a simple onestep hydrothermal route without using any surfactants. We successfully synthesize Co3O4 nanowires on Ni foam through a facile hydrothermal route. The as-fabricated samples deliver specific areal capacitance of 0.73 C cm−2 at 6 mA cm−2 (310.4 C g−1 at the current density of 1 A g−1) and cycle stability with capacitance retention of 80.3% after 6000 cycles. In addition, the asymmetric supercapacitors are prepared through the as-fabricated products and active carbon, which exhibits an energy density of 0.3
Data Loading...
