Size-Dependent Synthesis of Hollow Co3O4 Nanocubes Derived from Co-Fe PBA as Battery-Type Electrode Materials for Hybrid Supercapacitors. Issue 8 (30th August 2021)

• Record Type: Journal Article
• Authors: Peng, Zhiling; Wang, Wenqi; Zhao, Heming; Qi, Juncheng; Zhang, Huifang; Zhou, Chungui; Yan, Bing; Zhang, Zepeng
• Is Part Of: Journal of the Electrochemical Society. Volume 168:Issue 8(2021)
• Publication Date: 2021-08-30
• Subjects: Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/ac2020
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Hollow nanostructures with enlarged surface areas are highly attractive electrode materials for supercapacitors. In this work, the size-dependent synthesis of hollow Co3 O4 nanocubes via a facile ionic exchange reaction between Co-Fe Prussian blue analogues (PBAs) and alkali solution is reported. By adjusting the concentration of sodium citrate to control the reaction kinetics during nucleation and growth, four different sizes of Co-Fe PBAs were synthesized. It was also found that a Co-Fe PBA of about 140 nm can be easily converted into a well-defined internal hollow structure, while Co-Fe PBAs with smaller or larger sizes are challenged in generating a hollow structure. Benefitting from the inner voids and thin shell architecture, the derived hollow Co3 O4 nanocubes exhibit a high specific capacity of 296.6C cm −2 at 2 mA cm −2, and a rate capability of 64.5% when the current density is increased to 60 mA cm −2 . Furthermore, a hybrid supercapacitor (HSC) was fabricated with hollow Co3 O4 nanocubes as the cathode and activated carbon as the anode, respectively. The HSC provided a maximum energy density of 14.1 Wh kg −1 at 464.7 W kg −1 . Moreover, it retained the excellent cycling stability of 85.7% of the original capacity over 5000 continuous charging and discharging processes.