Ultrafine tin oxide on reduced graphene oxide as high-performance anode for sodium-ion batteries

•A nanohybrid based on ultrafine SnO2 and few-layered rGO has been prepared.•The nanohybrid exhibits excellent electrochemical Na-storage properties.•The rGO supplies combined conducting, buffering and dispersing effects.

Na-ion Battery is attractive alternative to Li-ion battery due to the natural abundance of sodium resource. Searching for suitable anode materials is one of the critical issues for Na-ion battery due to the low Na-storage activity of carbon materials. In this work, we synthesized a nanohybrid anode consisting of ultrafine SnO2 anchored on few-layered reduced graphene oxide (rGO) by a facile hydrothermal route. The SnO2/rGO hybrid exhibits a high capacity, long cycle life and good rate capability. The hybrid can deliver a high charge capacity of 324 mAh gSnO2−1 at 50 mA g−1. At 1600 mA g−1 (2.4C), it can still yield a charge capacity of 200 mAh gSnO2−1. After 100 cycles at 100 mA g−1, the hybrid can retain a high charge capacity of 369 mAh gSnO2−1. X-ray photoelectron spectroscopy, ex situ transmission electron microscopy and electrochemical impedance spectroscopy were used to investigate the origin of the excellent electrochemical Na-storage properties of SnO2/rGO.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide