Graphene supported alpha -MnO sub(2) nanocomposite cathodes for lithium ion batteries

• Published in: International journal of hydrogen energy Vol. 41; no. 16; pp. 6945 - 6953
• Main Authors: Cetinkaya, Tugrul, Tokur, Mahmud, Ozcan, Seyma, Uysal, Mehmet, Akbulut, Hatem
• Format: Journal Article
• Language: English
• Published: 04.05.2016
• Subjects: Cathodes; Constants; Current density; Electrodes; Graphene; Lithium-ion batteries; Nanocomposites; Scanning electron microscopy
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2015.12.092

In this study, Graphene/ alpha -MnO sub(2) nanocomposite cathodes were produced using ultrasonication and mechanical alloying facilities. Before production of Graphene/ alpha -MnO sub(2) composites, Graphene structure was fabricated by reduction of Graphene Oxide produced using Hummer's Method and alpha -MnO sub(2) nanowires was synthesized using microwave hydrothermal synthesis method. The effect of Graphene support on the electrochemical performance of the Graphene/ alpha -MnO sub(2) nanocomposite cathodes were investigated by dispersing different amounts of Graphene (10 wt.%, 30 wt.% and 50 wt.%) in the composite cathodes. Structures of the Graphene/ alpha -MnO sub(2) nanocomposites were characterized using X-ray diffraction (XRD) and Raman Spectroscopy techniques. Surface morphology of the electrodes was characterized using scanning electron microscopy (SEM). Electrochemical cycling tests of the Graphene/ alpha -MnO sub(2) nanocomposite cathodes were performed in the voltage range of 1.5 V-4.5 V at a constant current density of 50 mA/g (C/5). This study proved that Graphene enhance the electrochemical reaction of alpha -MnO sub(2) and provide stable cathode materials. Eventually, Graphene/ alpha -MnO sub(2) cathode containing 50 wt.% Graphene showed 225 mAh/g discharge capacity even after 200 cycles.