Formation of ultrafine three-dimensional hierarchical birnessite-type MnO2 nanoflowers for supercapacitor

• Published in: Journal of alloys and compounds 2014-09, Vol.607, p.245-250
• Main Authors: Yan, Dongliang, Zhang, Huan, Li, Shichao, Zhu, Guisheng, Wang, Zhongmin, Xu, Huarui, Yu, Aibing
• Format: Article
• Language: English
• Subjects: Cross-disciplinary physics: materials science; rheology; Energy storage materials; Exact sciences and technology; Materials science; Methods of nanofabrication; Nanostructured materials; Oxide materials; Physics; Supercapacitor; Ultrafine
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.04.077

•Ultrafine mesoporous birnessite-type MnO2 nanoflowers have been synthesized via a solution route.•Hierarchical MnO2 nanoflowers are made up of numerous two-dimensional ultrathin nanosheets.•MnO2 nanoflowers electrode exhibits superior electrochemical performance.•It is promising for supercapacitor application. Ultrafine (50–100nm in diameter) birnessite-type MnO2 nanoflowers assembled by numerous ultrathin nanosheets (3–6nm in thickness and 30–50nm in width) have been synthesized via a simple and scalable solution route under ambient conditions. The ratio of reactants plays a significant role in the formation of MnO2 nanoflowers and the as-prepared MnO2 hierarchical nanostructure exhibits excellent electrochemical performance with high specific capacitance (251.3Fg−1 at 0.5Ag−1) and superior cycling stability (only 7.5% SC loss after 10,000 cycling test) and good rate capability. The unique microstructures of MnO2 nanoflowers are responsible for their superior electrochemical properties, and thus it may be a promising for supercapacitor application.