Unexpected intercalation-dominated potassium storage in WS2 as a potassium-ion battery anode
Result description
Unexpected intercalation-dominated process is observed during K+ insertion in WS2 in a voltage range of 0.01-3.0 V. This is different from the previously reported two-dimensional (2D) transition metal dichalcogenides that undergo a conversion reaction in a low voltage range when used as anodes in potassium-ion batteries. Charge/discharge processes in the K and Na cells are studied in parallel to demonstrate the different ion storage mechanisms. The Na+ storage proceeds through intercalation and conversion reactions while the K+ storage is governed by an intercalation reaction. Owing to the reversible K+ intercalation in the van der Waals gaps, the WS2 anode exhibits a low decay rate of 0.07% per cycle, delivering a capacity of 103 mAh center dot g(-1) after 100 cycles at 100 mA center dot g-(1). It maintains 57% capacity at 800 mA center dot g(-1) and shows stable cyclability up to 400 cycles at 500 mA center dot g-(1). Kinetics study proves the facilitation of K+ transport is derived from the intercalation-dominated mechanism. Furthermore, the mechanism is verified by the density functional theory (DFT) calculations, showing that the progressive expansion of the interlayer space can account for the observed results.
Keywords
The result's identifiers
Result code in IS VaVaI
Alternative codes found
RIV/00216208:11310/19:10403771
Result on the web
https://link.springer.com/article/10.1007%2Fs12274-019-2543-0
DOI - Digital Object Identifier
Alternative languages
Result language
angličtina
Original language name
Unexpected intercalation-dominated potassium storage in WS2 as a potassium-ion battery anode
Original language description
Unexpected intercalation-dominated process is observed during K+ insertion in WS2 in a voltage range of 0.01-3.0 V. This is different from the previously reported two-dimensional (2D) transition metal dichalcogenides that undergo a conversion reaction in a low voltage range when used as anodes in potassium-ion batteries. Charge/discharge processes in the K and Na cells are studied in parallel to demonstrate the different ion storage mechanisms. The Na+ storage proceeds through intercalation and conversion reactions while the K+ storage is governed by an intercalation reaction. Owing to the reversible K+ intercalation in the van der Waals gaps, the WS2 anode exhibits a low decay rate of 0.07% per cycle, delivering a capacity of 103 mAh center dot g(-1) after 100 cycles at 100 mA center dot g-(1). It maintains 57% capacity at 800 mA center dot g(-1) and shows stable cyclability up to 400 cycles at 500 mA center dot g-(1). Kinetics study proves the facilitation of K+ transport is derived from the intercalation-dominated mechanism. Furthermore, the mechanism is verified by the density functional theory (DFT) calculations, showing that the progressive expansion of the interlayer space can account for the observed results.
Czech name
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Czech description
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Classification
Type
Jimp - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10403 - Physical chemistry
Result continuities
Project
—
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2019
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Nano Research
ISSN
1998-0124
e-ISSN
—
Volume of the periodical
12
Issue of the periodical within the volume
12
Country of publishing house
CN - CHINA
Number of pages
6
Pages from-to
2997-3002
UT code for WoS article
000494220000001
EID of the result in the Scopus database
2-s2.0-85074842422
Basic information
Result type
Jimp - Article in a specialist periodical, which is included in the Web of Science database
OECD FORD
Physical chemistry
Year of implementation
2019