RIS ID
22481
Abstract
This article introduces an effective, inexpensive, and industrially oriented approach to produce carbon-coated Si nanocomposites as high-capacity anode materials for use in rechargeable lithium-ion batteries. Initially, nanosized Si particles (nm) were mixed in a citric acid/ethanol solution via ultrasonication. This mixture was further spray-pyrolyzed in air at low processing temperature (300-500 C), resulting in a homogeneous layer of carbon coating on the surface of the spheroidal Si nanoparticles. The effects of the processing temperature on the amorphous carbon content, the thickness of the carbon-coating layer, and the homogeneity of the carbon coating were studied in detail. These parameters strongly influenced the electrochemical performance of the carbon-coated Si nanocomposites, as will be discussed below. Carbon-coated Si nanocomposites spray-pyrolyzed in air at 400 C show the best cycling performance, retaining a specific capacity of 1120 mA·h g-1 beyond 100 cycles, with a capacity fading of less than 0.4% per cycle. The beneficial effect of the carbon coating in enhancing the dimensional stability of the Si nanoparticles appears to be the main reason for this markedly improved electrochemical performance.
Publication Details
Ng, S., Wang, J., Wexler, D., Chew, S. Y. Liu, H. K. (2007). Amorphous carbon-coated silicon nanocomposites: a low-temperature synthesis via spray pyrolysis and their application as high-capacity anodes for lithium-ion batteries. The Journal of Physical Chemistry Part C: Nanomaterials and Interfaces, 111 (29), 11131-11138. Copyright 2007 the American Chemical Society.