nn8b03188_si_001.pdf (2.61 MB)
Cobalt Disulfide Nanoparticles Embedded in Porous Carbonaceous Micro-Polyhedrons Interlinked by Carbon Nanotubes for Superior Lithium and Sodium Storage
journal contribution
posted on 2018-06-25, 00:00 authored by Yuan Ma, Yanjiao Ma, Dominic Bresser, Yuanchun Ji, Dorin Geiger, Ute Kaiser, Carsten Streb, Alberto Varzi, Stefano PasseriniTransition metal sulfides are appealing
electrode materials for lithium and sodium batteries owing to their
high theoretical capacity. However, they are commonly characterized
by rather poor cycling stability and low rate capability. Herein,
we investigate CoS2, serving as a model compound. We synthesized
a porous CoS2/C micro-polyhedron composite entangled in
a carbon-nanotube-based network (CoS2-C/CNT), starting
from zeolitic imidazolate frameworks-67 as a single precursor. Following
an efficient two-step synthesis strategy, the obtained CoS2 nanoparticles are uniformly embedded in porous carbonaceous micro-polyhedrons,
interwoven with CNTs to ensure high electronic conductivity. The CoS2-C/CNT nanocomposite provides excellent bifunctional energy
storage performance, delivering 1030 mAh g–1 after
120 cycles and 403 mAh g–1 after 200 cycles (at
100 mA g–1) as electrode for lithium-ion (LIBs)
and sodium-ion batteries (SIBs), respectively. In addition to these
high capacities, the electrodes show outstanding rate capability and
excellent long-term cycling stability with a capacity retention of
80% after 500 cycles for LIBs and 90% after 200 cycles for SIBs. In situ X-ray diffraction reveals a significant contribution
of the partially graphitized carbon to the lithium and at least in
part also for the sodium storage and the report of a two-step conversion
reaction mechanism of CoS2, eventually forming metallic
Co and Li2S/Na2S. Particularly the lithium storage
capability at elevated (dis-)charge rates, however, appears to be
substantially pseudocapacitive, thus benefiting from the highly porous
nature of the nanocomposite.
History
Usage metrics
Categories
Keywords
LIBSIBconversion reaction mechanismCoS 2electrodecapacityrate capability200 cyclesCoS 2 nanoparticlesSodium Storage Transition metal sulfideszeolitic imidazolate frameworks -67Porous Carbonaceous Micro-Polyhedrons Interlinkedbifunctional energy storage performanceCobalt Disulfide Nanoparticlescycling stabilityCNTlithium storage capability
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC