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Indexed by:期刊论文

Date of Publication:2014-01-03

Journal:CHEMISTRY-A EUROPEAN JOURNAL

Included Journals:SCIE、EI、PubMed、Scopus

Volume:20

Issue:1

Page Number:139-145

ISSN No.:0947-6539

Key Words:carbon; electrodes; iron oxide; lithium; lithium-ion batteries; pyrolysis

Abstract:In this study, a method is developed to fabricate Fe3O4@C particles with a coaxial and penetrated hollow mesochannel based on the concept of confined nanospace pyrolysis. The synthesis involves the production of a polydopamine coating followed by a silica coating on a rod-shaped -FeOOH nanoparticle, and subsequent treatment by using confined nanospace pyrolysis and silica removal procedures. Typical coaxial hollow Fe3O4@C possesses a rice-grain morphology and mesoporous structure with a large specific surface area, as well as a continuous and flexible carbon shell. Electrochemical tests reveal that the hollow Fe3O4@C with an open-ended nanostructure delivers a high specific capacity (ca. 864mAhg(-1) at 1Ag(-1)), excellent rate capability with a capacity of about 582mAhg(-1) at 2Ag(-1), and a high Coulombic efficiency (>97%). The excellent electrochemical performance benefits from the hollow cavity with an inner diameter of 18nm and a flexible carbon shell that can accommodate the volume change of the Fe3O4 during the lithium insertion/extraction processes as well as the large specific surface area and open inner cavity to facilitate the rapid diffusion of lithium ions from electrolyte to active material. This fabrication strategy can be used to generate a hollow or porous metal oxide structure for high-performance Li-ion batteries.