Premium
Challenges of “Going Nano”: Enhanced Electrochemical Performance of Cobalt Oxide Nanoparticles by Carbothermal Reduction and In Situ Carbon Coating
Author(s) -
Bresser Dominic,
Paillard Elie,
Niehoff Philip,
Krueger Steffen,
Mueller Franziska,
Winter Martin,
Passerini Stefano
Publication year - 2014
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201400092
Subject(s) - carbothermic reaction , cobalt , nanoparticle , coating , electrochemistry , cobalt oxide , materials science , in situ , carbon fibers , chemical engineering , nano , oxide , reduction (mathematics) , nanotechnology , chemistry , electrode , metallurgy , composite material , organic chemistry , carbide , composite number , engineering , geometry , mathematics
The electrochemical performance of nano‐ and micron‐sized Co 3 O 4 is investigated, highlighting the substantial influence of the specific surface area on the obtainable specific capacities as well as the cycling stability. In fact, Co 3 O 4 materials with a high surface area (i.e. a small particle size) show superior specific features, which are, however, accompanied by a rapid capacity fading, owing to the increased formation of an insulating polymeric surface film that results from transition‐metal‐catalyzed electrolyte decomposition. The simultaneous coating with carbon of Co 3 O 4 nanoparticles and in situ reduction of the Co 3 O 4 by a carbothermal route yields a CoOCoC nanocomposite. The formation of this material substantially enhances the long‐term cycling stability and coulombic efficiency of the lithium‐ion active material used. Although the metallic cobalt enhances the electronic conductivity within the electrode and remains electrochemically inactive (as revealed by in situ powder X‐ray diffraction analysis), it might have a detrimental effect on the long‐term cycling stability by catalytically inducing continuous electrolyte decomposition.