Issue 10, 2010

Enhancement of long stability of sulfur cathode by encapsulating sulfur into micropores of carbon spheres

Abstract

To enhance the long stability of sulfur cathode for a high energy lithiumsulfur battery system, a sulfurcarbon sphere composite was prepared by encapsulating sulfur into micropores of carbon spheres by thermal treatment of a mixture of sublimed sulfur and carbon spheres. The elemental sulfur exists as a highly dispersed state inside the micropores of carbon spheres with a large surface area and a narrow pore distribution, based on the analyses of the X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), thermogravimetry (TG) and local element line-scanning. It is demonstrated from galvanostatic discharge–charge process, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) that the sulfurcarbon sphere composite has a large reversible capacity and an excellent high rate discharge capability as cathode materials. In particular, the sulfurcarbon sphere composite with 42 wt% sulfur presents a long electrochemical stability up to 500 cycles, based on the constrained electrochemical reaction inside the narrow micropores of carbon spheres due to strong adsorption. Therefore, the electrochemical reaction constrained inside the micropores proposed here would be the dominant factor for the enhanced long stability of the sulfur cathode. The knowledge acquired in this study is important not only for the design of efficient new electrode materials, but also for understanding the effect of the micropores on the electrochemical cycle stability.

Graphical abstract: Enhancement of long stability of sulfur cathode by encapsulating sulfur into micropores of carbon spheres

Supplementary files

Article information

Article type
Paper
Submitted
08 Feb 2010
Accepted
15 Jun 2010
First published
16 Aug 2010

Energy Environ. Sci., 2010,3, 1531-1537

Enhancement of long stability of sulfur cathode by encapsulating sulfur into micropores of carbon spheres

B. Zhang, X. Qin, G. R. Li and X. P. Gao, Energy Environ. Sci., 2010, 3, 1531 DOI: 10.1039/C002639E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements