Template-free rapid sonochemical synthesis of spherical α-MnO2 nanoparticles for high-energy supercapacitor electrode. Issue 14 (1st October 2018)

• Record Type: Journal Article
• Authors: Sankar, S.; Inamdar, Akbar I.; Im, Hyunsik; Lee, Sejoon; Kim, Deuk Young
• Is Part Of: Ceramics international. Volume 44:Issue 14(2018)
• Page Start: 17514
• Page End: 17521
• Publication Date: 2018-10-01
• Subjects: Sonochemical preparation -- α-MnO2 -- Nanoparticles -- Electrode -- Supercapacitor; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.05.207
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Spherical MnO2 nanoparticles were synthesized at room temperature via template-free sonochemical reduction of potassium permanganate using a reducing agent of polyethylene glycol under two different time durations ( i.e., 15 min (M1) and 30 min (M2)). The M2 sample exhibited the α-phase of the tetragonal MnO2 structure, whereas the M1 sample showed the δ-MnO2 phase. For microstructural analyses, the M2 sample revealed a spherical structure of the nanoparticles with an average grain size of 20–30 nm. When using spherical MnO2 nanoparticles ( i.e., M2) as an electrode material for the supercapacitor device, the maximum specific capacitance of 136 F/g was observed at the current density of 0.5 A/g. The device displayed an excellent cyclic stability of 72% after 5000 charge/discharge cycles, and showed a high energy density up to 38.3 Wh/kg. These results suggest that the sonochemically-synthesized spherical MnO2 nanoparticles could be used as a suitable electrode material for high-energy electrochemical supercapacitors. Graphical abstract: fx1