Facile One-Pot Synthesis of LiMnO2 Nanowire-Graphene Nanoplatelet Composites and Their Applications in Battery-Like Electrodes for High Performance Electrochemical Capacitors

Abstract

In this work, the well-dispersed LiMnO2 nanowires of diameter 100nm were successfully prepared via a simple one-pot hydrothermal method. The morphology of the nanowires during their growth was dependent on the reaction time. The LiMnO2 nanowires were possibly formed by a nucleation and regrowth process. The LiMnO2 nanowires-graphene nanoplatelets (LiMnO2 nanowires-GNP) composite was then prepared by the direct milling of one-dimensional LiMnO2 nanowires and two-dimensional GNP. The LiMnO2 nanowires-GNP composite was employed as an electrode material to investigate its electrochemical performance. The LiMnO2 nanowires-GNP composite exhibited an outstanding mass-specific capacitance of 147Fg(-1) at 5mVs(-1), as revealed by cyclic voltammetry measurement. This was more than three times higher than that exhibited by LiMnO2 nanowires (41Fg(-1)). The cycling performance of LiMnO2 nanowires-GNP electrode revealed a capacitance retention of 86% after 1000 charge-discharge cycles at 5Ag(-1), which was superior to that exhibited by the LiMnO2 nanowires. Besides, the resistance of the LiMnO2 nanowires-GNP was lower than that of LiMnO2 nanowires, demonstrating that these hybrids could be considered as next generation electrode materials for electrochemical energy storage and conversion devices.