Synthesis of freestanding binder- and additive-free carbon nanofiber with graphene-wrapped Nb2O5composite anode for lithium-ion batteries

Doo-Won Kim; So Yeun Kim; Kap Seung Yang

doi:10.1088/1361-6528/ac162d

Synthesis of freestanding binder- and additive-free carbon nanofiber with graphene-wrapped Nb₂O₅composite anode for lithium-ion batteries

Nanotechnology. 2021 Oct 20;33(1). doi: 10.1088/1361-6528/ac162d.

Authors

Doo-Won Kim^{1

2}, So Yeun Kim³, Kap Seung Yang^{2

3}

Affiliations

¹ Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Chudong-ro 92, Bongdong-eup, Wanju-gun, Jeollabukdo 55324, Republic of Korea.
² Department of Polymer Engineering, Graduate School, School of Polymer Science and Engineering & Alan G. MacDiarmid Energy Research Institute, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea.
³ Carbon Composite Materials R&D center HPK Inc., Ballyong-ro 109, Deokjin-gu, Jeonju-si, Jeollabukdo 54853, Republic of Korea.

PMID: 34284372
DOI: 10.1088/1361-6528/ac162d

Abstract

Niobium pentoxide (Nb₂O₅)-based materials have attracted significant interest for application in diverse fields. Unfortunately, the employment of these materials as electrodes of lithium-ion batteries (LIBs) is limited by several inherent drawbacks. The present study demonstrated the synthesis of composites comprising homogeneous graphene-wrapped niobium pentoxide (GNbO) encapsulated in carbon nanofibers (CNFs) for utilization as binder- and additive-free anodes in LIBs. The composites were synthesized via electrospinning and subsequent carbonization; the presence of graphene (G) ensured the homogenous dispersion of the Nb₂O₅particles in the CNF matrix. The CNFs formed a highly conductive network that resulted in high physical flexibility, electrical conductivity, and structural stability during charge-discharge cycles, thereby facilitating rapid ion/electron transmission. Consequently, the CNF/GNbO composite anodes exhibited outstanding electrochemical performances. CNF/GNbO_5 (one of the synthesized composites with an Nb₂O₅concentration of 5 wt% relative to GO) delivered a specific capacity of 361 mAh g^-1after 100 cycles, corresponding to a capacity retention of 58.3%. In addition, it exhibited an excellent rate capability with a capacity of 317 mAh g^-1at 10 C. The outcomes of the present study will facilitate the extensive application of the synthesized composites as high-performance anodes in next-generation LIBs.

Keywords: anode; carbon nanofiber; electrospinning; graphene warping; lithium-ion battery; niobium pentoxide.