Unveiling of the energy storage mechanisms of multi -modified (Nb2O5@C)/rGO nanoarrays as anode for high voltage supercapacitors with formulated ionic liquid electrolytes
Type
ArticleAuthors
Zhang, JiaheZhang, Haitao
Zhang, Yaqin
Zhang, Junwei
He, Hongyan
Zhang, Xixiang
Shim, Jae Jin
Zhang, Suojiang
KAUST Department
Material Science and Engineering ProgramPhysical Science and Engineering (PSE) Division
Date
2019-04-29Online Publication Date
2019-04-29Print Publication Date
2019-08Permanent link to this record
http://hdl.handle.net/10754/656467Metadata
Show full item recordAbstract
A better understanding of the energy-storage mechanisms in complex pseudocapacitive nanostructures is essential to improve the performances of nanohybrid supercapacitors. In this study, highly interface modified Nb2O5 nanoarrays, attached to graphene nanosheets, were carefully designed and synthesized. The electrochemical performances were evaluated in an organic electrolyte, a formulated ionic-liquid mixture electrolyte, and a nanocomposite ionogel electrolyte, respectively. The capacitive and faradaic storage contributions were assessed qualitatively in diverse electrolytes at various temperatures. The capacitive contribution in the ionic liquid electrolyte was found to rise with increasing temperature. A molecular dynamics simulation proved that the increased diffusion coefficient of large ions was much more pronounced than that of the small Li+ ions. A carefully optimized quasi-solid-state lithium ion capacitor, fabricated using a (Nb2O5@C)/rGO nanoarchitecture as the anode and an ionic liquid gel separator, delivered an energy density of 101 Wh kg−1 and a power density of 24 kW kg−1 at 60 °C. The efficient coupling between the nanohybrids and a complex ionogel electrolyte opens a new window for the rational design of high energy-density supercapacitors.Citation
Zhang, J., Zhang, H., Zhang, Y., Zhang, J., He, H., Zhang, X., … Zhang, S. (2019). Unveiling of the energy storage mechanisms of multi -modified (Nb2O5@C)/rGO nanoarrays as anode for high voltage supercapacitors with formulated ionic liquid electrolytes. Electrochimica Acta, 313, 532–543. doi:10.1016/j.electacta.2019.04.160Sponsors
This work was financially supported by the National Key Research and Development Program of China (No.2016YFB0100303), the Major Program of National Natural Science Foundation of China (No. 21890762), the National Natural Science Foundation of China (No. 21878308) and the International Cooperation and Exchange of the National Natural Science Foundation of China (51561145020).Publisher
Elsevier BVJournal
Electrochimica ActaAdditional Links
https://linkinghub.elsevier.com/retrieve/pii/S0013468619308576Scopus Count
![NOTICE: this is the author’s version of a work that was accepted for publication in Electrochimica Acta. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Electrochimica Acta, [[Volume], [Issue], (2019-08-01)] DOI: 10.1016/j.electacta.2019.04.160 . © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/](/themes/OR//images/creativecommons/cc-by-nc-nd.png)
Except where otherwise noted, this item's license is described as NOTICE: this is the author’s version of a work that was accepted for publication in Electrochimica Acta. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Electrochimica Acta, [[Volume], [Issue], (2019-08-01)] DOI: 10.1016/j.electacta.2019.04.160 . © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
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