Abstract
The electrochemical properties of hollow cobalt oxide and cobalt selenide microspheres are studied for the first time as anode materials for Na-ion batteries. Hollow cobalt oxide microspheres prepared by one-pot spray pyrolysis are transformed into hollow cobalt selenide microspheres by a simple selenization process using hydrogen selenide gas. Ultrafine nanocrystals of Co3O4 microspheres are preserved in the cobalt selenide microspheres selenized at 300 °C. The initial discharge capacities for the Co3O4 and cobalt selenide microspheres selenized at 300 and 400 °C are 727, 595, and 586 mA h g-1, respectively, at a current density of 500 mA g-1. The discharge capacities after 40 cycles for the same samples are 348, 467, and 251 mA h g-1, respectively, and their capacity retentions measured from the second cycle onward are 66, 91, and 50%, respectively. The hollow cobalt selenide microspheres have better rate performances than the hollow cobalt oxide microspheres.
Original language | English |
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Pages (from-to) | 6449-6456 |
Number of pages | 8 |
Journal | ACS Applied Materials and Interfaces |
Volume | 8 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2016 Mar 16 |
Keywords
- Na-ion battery
- cobalt oxide
- cobalt selenide
- energy storage
- nanostructure
ASJC Scopus subject areas
- Materials Science(all)