Premium
Carbon Nanolayer‐Coated Na 3 V 2 (PO 4 ) 3 Nanocrystals Embedded in Conductive Carbon Matrix as High‐Performance Cathode for Sodium‐Ion Batteries
Author(s) -
Wan Xin,
Liu Kelu,
Lei Ping,
Zheng Wenting,
Xiang Xingde,
Sun Molong
Publication year - 2018
Publication title -
chemelectrochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.182
H-Index - 59
ISSN - 2196-0216
DOI - 10.1002/celc.201800782
Subject(s) - materials science , graphene , carbon fibers , cathode , scanning electron microscope , chemical engineering , electrochemistry , nanocrystal , nanostructure , coating , fourier transform infrared spectroscopy , nanotechnology , electrode , composite material , composite number , chemistry , engineering
Na 3 V 2 (PO 4 ) 3 is a promising cathode material for sodium‐ion batteries. However, the design of appropriate carbon coatings is necessary for improving the Na‐storage performance of this material to overcome the intrinsically low electron conductivity and therefore sluggish reaction kinetics. Herein, carbon nanolayer‐coated Na 3 V 2 (PO 4 ) 3 nanocrystals embedded in a conductive carbon matrix (NVP/C) are fabricated by using a facile in‐situ synthesis method with controlled utilization of graphene‐oxide nanosheets. Structural and electrochemical properties of the as‐synthesized NVP/C material are analyzed by combining X‐ray diffraction, Fourier‐transform infrared spectroscopy, scanning electron microscope, transition electron microscope, and electrochemical measurements. The optimized NVP/C material exhibits a unique nanostructure consisting of Na 3 V 2 (PO 4 ) 3 nanocrystals with an average size of ∼60 nm and carbon nanolayers with uniform thickness of ∼5 nm. As electrode, the material delivers a high reversible capacity of 114.8 mAh g −1 at 0.2 C, superior high‐rate capability with a discharge capacity of 101.8 mAh g −1 at 10 C, and excellent cycling performance with capacity retention of 91 % after 1000 cycles. The finding indicates that constructing carbon‐coating nanolayers and a conductive carbon matrix is an important strategy to achieve high‐quality NVP/C material for advanced sodium‐ion batteries.