Format

Send to

Choose Destination
See comment in PubMed Commons below
ACS Nano. 2010 Apr 27;4(4):2233-41. doi: 10.1021/nn901632g.

Nanostructured hybrid silicon/carbon nanotube heterostructures: reversible high-capacity lithium-ion anodes.

Author information

1
Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.

Abstract

Lithium-ion batteries have witnessed meteoric advancement the last two decades. The anode area has seen unprecedented research activity on Si and Sn, the two anode alternatives to currently used carbon following the initial seminal work by Fuji on tin oxide nanocomposites. Recent reports on silicon nanowires, porous Si, and amorphous Si coatings on graphite nanofibers (GNF) have been very encouraging. High capacity and long cycle life anodes are still, however, elusive and much needed to meet the ever increasing energy storage demands of modern society. Herein, we report for the first time the synthesis of novel 1D heterostructures comprising vertically aligned multiwall CNTs (VACNTs) containing nanoscale amorphous/nanocrystalline Si droplets deposited directly on VACNTs with clearly defined spacing using a simple two-step liquid injection CVD process. A hallmark of these single reactor derived heterostructures is an interfacial amorphous carbon layer anchoring the nanoscale Si clusters directly to the VACNTs. The defined spacing of nanoscale Si combined with their tethered CNT architecture allow for the silicon to undergo reversible electrochemical alloying and dealloying with Li with minimal loss of contact with the underlying CNTs. The novel heterostructures thus exhibit impressive reversible stable capacities approximately 2050 mAh/g with very good rate capability and an acceptable first cycle irreversible loss approximately 20% comparable to graphitic anodes indicating their promise as high capacity Li-ion anodes. Although warranting further research, particularly with regard to long-term cycling, it can be envisaged that optimization of this simple approach could lead to reversible high capacity next generation Li-ion anodes.

PMID:
20364846
DOI:
10.1021/nn901632g
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for American Chemical Society
    Loading ...
    Support Center