Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 6, Issue 13, Pages 10754-10762Publisher
AMER CHEMICAL SOC
DOI: 10.1021/am502638d
Keywords
energy storage; electrochemical pseudocapacitor; MnO2 nanowires; hydrothermal synthesis; Fe(CN)(6)(4-)/Fe(CN)(6)(3-) redox couple
Funding
- CSIR via TAPSUN [NWP0056]
Ask authors/readers for more resources
Low electronic conductivity and slow faradic processes limit the performance of MnO2 as an electrochemical pseudocapacitor with respect to cycling and power density. Herein, we report preparation of single-phase alpha-MnO2, composed of an interconnected nanowire network with cocoonlike morphology, and its application as electrode in a symmetric aqueous supercapacitor. Increased effective surface area, coexistence of micropores and mesopores, and enhanced electron transport in these nanowire networks result in a specific pseudocapacitance (C-S) of 775 F.g(-1) in 3 M KOH, derived from cyclic voltammetry in the potential window of -1 to +1 V at a scan rate of 2 mV.s(-1), the highest reported for two-electrode symmetric configuration. Furthermore, introduction of K4Fe(CN)(6) as a redox-active additive to KOH results in similar to 7 times increase in energy density at a power density of similar to 6000 W. kg(-1). The presence of the Fe(CN)(6)(4-)/Fe(CN)(6)(3-) redox couple provides an electron buffer source compensating for the slow faradic reactions. The results demonstrate that this simple approach might be an effective way to enhance the redox kinetics and reversibility of transition metal oxide-based pseudocapacitors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available