Graphene-bound Na3V2(PO4)3 film electrode with excellent cycle and rate performance for Na-ion batteries

Autor: Xiaqing Chang, Mingyu Feng, Ning Sun, Bin Xu, Jiashun Zhao, Ran Wang, Qizhen Zhu, Yibiao Guan
Rok vydání: 2018
Předmět:
Zdroj: Electrochimica Acta. 269:282-290
ISSN: 0013-4686
DOI: 10.1016/j.electacta.2018.03.004
Popis: Na3V2(PO4)3 is an attractive electrode material for Na-ion batteries due to high ionic conductivity and good stability, but suffers from low electronic conductivity. Here, a graphene-bound Na3V2(PO4)3 film is fabricated by simple vacuum co-filtration and thermal treatment, which can be directly used as both cathode and anode for Na-ion batteries. In the film, Na3V2(PO4)3 nanoparticles are homogeneously bounded in a 3D continuous graphene network. As graphene acts as binder, conductive agent, and current collector simultaneously, the content of Na3V2(PO4)3 can easily reach up to about 93.3 wt%, promising a superior capacity calculated based on the total mass of the electrode. Furthermore, the 3D conductive graphene provides efficient electron pathways and buffers volume change during cycling. Therefore, the graphene-bound Na3V2(PO4)3 electrode exhibits high capacity (114.6 mAh g−1 at 1 C as cathode, 69.1 mAh g−1 at 50 mA g−1 as anode), ultra-long cycle stability (only about 0.005% of the capacity is decayed per cycle during 10 000 cycles) and excellent rate performance (89.7 mAh g−1 at 30 C as cathode, 42.3 mAh g−1 at 2 A g−1 as anode). As a result, we believe the graphene-bound Na3V2(PO4)3 film is a promising candidate for Na-ion batteries.
Databáze: OpenAIRE
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