Reduced graphene oxide/carbon nanotubes sponge: A new high capacity and long life anode material for sodium-ion batteries

• Published in: Journal of power sources 2016-06, Vol.316, p.132-138
• Main Authors: Yan, Dong, Xu, Xingtao, Lu, Ting, Hu, Bingwen, Chua, Daniel H.C., Pan, Likun
• Format: Article
• Language: English
• Subjects: Anodes; Carbon nanotubes; Charge; Graphene; High capacity; Long life cycling; Oxides; Rechargeable batteries; Reduced graphene oxide/carbon nanotubes sponge; Sodium-ion batteries; Sponges; X-rays
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2016.03.050

Reduced graphene oxide/carbon nanotubes (CNTs) sponge (GCNTS) is fabricated via a simple freeze drying of graphene oxide/CNTs mixed solution and subsequent thermal treatment in nitrogen atmosphere, and used as anodes for sodium-ion batteries (SIBs) for the first time. The morphology, structure and electrochemical performance of GCNTS are characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that GCNTS with 20 wt % CNTs has a highest charge capacity of 436 mA h g−1 after 100 cycles at a current density of 50 mA g−1 and even at a high current density of 10 A g−1, a capacity of 195 mA h g−1 is maintained after 7440 cycles. The high capacity, excellent rate performance and long life cycling enable the GCNTS to be a promising candidate for practical SIBs. •Graphene/carbon nanotubes sponge was fabricated via a simple freeze drying method.•The hybrid sponge was employed as anode materials of sodium ion batteries.•The hybrid sponge exhibits high capacity and superior long life cycling stability.