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Title: In situ synthesis and in operando NMR studies of a high-performance Ni 5 P 4 -nanosheet anode
Nickel phosphide (Ni 5 P 4 ) nanosheets are synthesized using in situ chemical vapor deposition of P on Ni foam. The thickness of the as-synthesized Ni 5 P 4 film is determined to be ∼5 nm, using atomic force microscopy (AFM). The small thickness shortens the diffusion path of Li ions and results in fast ion transport. In addition, the 2D Ni 5 P 4 nanosheets seamlessly connect to the Ni foam, which facilitates electron transfer between Ni 5 P 4 and the Ni current collector. Therefore, the binder/carbon free-nickel supported Ni 5 P 4 shows fast rate performance as an anode for lithium-ion batteries (LIBs). The specific capacity of 2D Ni 5 P 4 is obtained as 600 mA h g −1 at a cycling rate of 0.1C, approaching the theoretical capacity of 768 mA h g −1 . Even at a rate of 0.5C, the capacity remains as 450 mA h g −1 over 100 cycles. A capacity >100 mA h g −1 is retained at a very high rate of 20C. Ni 5 P 4 also exhibits a low voltage of ∼0.5 V with respect to Li metal, which makes it a suitable negative electrode for LIBs. In operando 31 P NMR and 7 Li NMR are employed to probe the lithiation and de-lithiation mechanisms upon electrochemical cycling.  more » « less
Award ID(s):
1808517
NSF-PAR ID:
10136462
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
6
Issue:
44
ISSN:
2050-7488
Page Range / eLocation ID:
22240 to 22247
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Acknowledgment

    This work was partially supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.

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