Hierarchically nanostructured MnO2 electrodes for pseudocapacitor application. Issue 104 (31st October 2016)

• Record Type: Journal Article
• Authors: Ryu, Ilhwan; Kim, Green; Yoon, Hajin; Ahn, Sang Jung; Yim, Sanggyu
• Is Part Of: RSC advances. Volume 6:Issue 104(2016)
• Page Start: 102814
• Page End: 102820
• Publication Date: 2016-10-31
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra22841k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The supercapacitive properties of hierarchically nanostructured manganese oxide (MnO2 ) electrodes were investigated. Abstract : The supercapacitive properties of hierarchically nanostructured manganese oxide (MnO2 ) electrodes were investigated. The hierarchical MnO2 nanostructures consisting of nanowires in a small length scale and inverse-opal nanostructures in a large length scale were successfully fabricated using a combination of colloidal nanosphere lithography and cyclic voltammetric deposition. A maximum specific capacitance, C sp, of 714 F g −1 at the scan rate of 10 mV s −1 was obtained, which was significantly larger than 556 F g −1 observed for the MnO2 electrode with simple nanowire structures. The enhancement of the C sp value is attributed to the lower charge-transfer and diffusive resistance of the hierarchical nanostructures, which was estimated by electrochemical impedance measurements. The other capacitive properties were also improved considerably. The C sp retention for the hierarchical nanostructure electrode after 5000 charge–discharge cycles was 75.4%, and the voltammetric response at high scan rates was 1.8 times larger than that for the simple nanowire electrode.