Abstract
Metal selenides are considered as a group of promising candidates as the anode material for sodium-ion batteries due to their high theoretical capacity. However, the intrinsically low electrical and ionic conductivities as well as huge volume change during the charge-discharge process give rise to an inferior sodium storage capability, which severely hinders their practical application. Herein, we fabricated In2Se3/CoSe2 hollow nanorods composed of In2Se3/CoIn2/CoSe2 by growing cobalt-based zeolitic imidazolate framework ZIF-67 on the surface of indium-based metal-organic framework MIL-68, followed by in situ gaseous selenization. Because of the CoIn2 alloy phase in between In2Se3 and CoSe2, a heterostructure consisting of two alloy/selenide interfaces has been successfully constructed, offering synergistically enhanced electrical conductivity, Na diffusion process, and structural stability, in comparison to the single CoIn2-free interface with only two metal selenides. As expected, this nanoconstruction delivers a high reversible capacity of 297.5 and 205.5 mAh g-1 at 5 and 10 A g-1 after 2000 cycles, respectively, and a superior rate performance of 371.6 mAh g-1 at even 20 A g-1.
Original language | English |
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Pages (from-to) | 13307-13318 |
Number of pages | 12 |
Journal | ACS Nano |
Volume | 15 |
Issue number | 8 |
Early online date | 23 Jul 2021 |
DOIs | |
Publication status | Published - 24 Aug 2021 |
Externally published | Yes |
Funding
This work was financially supported by Fundamental Research Funds for the Central Universities (ZYGX2019J030). Q.Y. acknowledges the funding support from Singapore MOE AcRF Tier 1 grant no. 2020-T1-001-031.
Keywords
- anode material
- heterostructure
- metal selenide
- multi-interface
- sodium-ion battery