High performance sodium-ion full battery based on one-dimensional nanostructures: the case of Na0.44MnO2 cathode and MoS2 anode

Abstract

Transition metal oxides have been considered as one of the most promising cathode candidates for sodium ion batteries (SIBs). Tunnel type Na0.44MnO2, a typical cathode material for sodium ion battery, shows hopeful potential for future practical SIBs as large-scale electric energy storage system due to the low-cost and environment-friendly virtues. However, poor cyclability and rate performance of Na0.44MnO2 ascribed to the slow kinetic and structural degradation have limited its practical application. Herein, single crystalline hinged nanorod shaped Na0.44MnO2 (NMO-HNR) is designed by simple solid reaction. By testing the electrochemical performances of NMO-HNR samples which are synthesized at different annealing temperatures, the effects of grain size and crystallinity on electrochemical properties are investigated in detail. Thanks to the robust structure of hinged nanorod which is identified by structural and morphological characteristics after deep cycling, all the samples exhibit outstanding cyclability. Especially, the optimized NMO-HNR-900 material could deliver prominent capacity retention of 93.6% after cycling 1800 cycles at 2 A g−1. More importantly, the full battery performance based on Na0.44MnO2 cathode and MoS2 anode is first reported in this work. As a consequence, NMO-HNR-900//Co9S8@MoS2 HNT full-cell can deliver a decent cycling property with a capacity retention of 72.1% after 80 cycles.