Abstract
This paper presents a hierarchical yolk–shell-structured microsphere comprising a hierarchical carbon nanotube (CNT)-(NiCo)O/C yolk and an embossed hollow thin shell (hereafter denoted as CNT-(NiCo)O/C microsphere) prepared by a one-pot spray pyrolysis process for potential use as an anode in lithium-ion batteries. During spray pyrolysis, the hierarchical CNT-(NiCo)O/C yolk, whose frame is linked with CNTs, is formed by mutual binding of the CNTs and size-controlled polystyrene (PS) nanobeads and subsequent selective decomposition of these nanobeads. Further, phase separation of melted poly(vinylpyrrolidone) facilitates the formation of the hollow shell. The discharge capacity of the CNT-(NiCo)O/C microspheres after 1000 cycles at an extremely high current density of 5.0 A g−1 is 598 mA h g−1. The CNT-(NiCo)O/C microspheres show reversible discharge capacities of 886, 709, 509, and 294 mA h g−1 at current densities of 0.5, 5, 20, and 50 A g−1, respectively. The unique nanostructure of the CNT-(NiCo)O/C microspheres with high electrical conductivity promotes the transfer kinetics of electrons and Li+ ions, which consequently leads to their improved electrochemical performances.
Original language | English |
---|---|
Pages (from-to) | 438-447 |
Number of pages | 10 |
Journal | Chemical Engineering Journal |
Volume | 368 |
DOIs | |
Publication status | Published - 2019 Jul 15 |
Bibliographical note
Funding Information:This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) ( NRF-2018R1A4A1024691 , NRF-2017M1A2A2087577 , and NRF-2018R1D1A3B07042514 )
Publisher Copyright:
© 2019 Elsevier B.V.
Keywords
- (Ni,Co)O solid solution
- Anode materials
- Lithium ion batteries
- Spray pyrolysis
- Yolk-shell
ASJC Scopus subject areas
- General Chemistry
- Environmental Chemistry
- General Chemical Engineering
- Industrial and Manufacturing Engineering