Understanding Capacitance Variation in Sub-nanometer Pores by in Situ Tuning of Interlayer Constrictions

The contribution of subnanometer pores in carbon electrodes to the charge-storage mechanism in supercapacitors has been the subject of intense debate for over a decade. Here, we provide a model system based on graphene oxide, which employs interlayer constrictions as a model for pore sizes that can...

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Published inACS nano Vol. 10; no. 1; pp. 747 - 754
Main Authors Galhena, Dona T. L, Bayer, Bernhard C, Hofmann, Stephan, Amaratunga, Gehan A. J
Format Journal Article
LanguageEnglish
Published United States American Chemical Society 26.01.2016
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Abstract The contribution of subnanometer pores in carbon electrodes to the charge-storage mechanism in supercapacitors has been the subject of intense debate for over a decade. Here, we provide a model system based on graphene oxide, which employs interlayer constrictions as a model for pore sizes that can be both controllably tuned and studied in situ during supercapacitor device use. Correlating electrochemical performance and in situ tuning of interlayer constrictions, we observe a peak in specific capacitance when interlayer constriction size reaches the diameters of unsolvated ions, supporting the hypothesized link between loss of ion solvation shell and anomalous capacitance increase for subnanometer pores.
AbstractList The contribution of subnanometer pores in carbon electrodes to the charge-storage mechanism in supercapacitors has been the subject of intense debate for over a decade. Here, we provide a model system based on graphene oxide, which employs interlayer constrictions as a model for pore sizes that can be both controllably tuned and studied in situ during supercapacitor device use. Correlating electrochemical performance and in situ tuning of interlayer constrictions, we observe a peak in specific capacitance when interlayer constriction size reaches the diameters of unsolvated ions, supporting the hypothesized link between loss of ion solvation shell and anomalous capacitance increase for subnanometer pores.
Author Hofmann, Stephan
Galhena, Dona T. L
Amaratunga, Gehan A. J
Bayer, Bernhard C
AuthorAffiliation Faculty of Physics
University of Vienna
Electrical Engineering Division, Department of Engineering
University of Cambridge
Sri Lanka Institute of Nanotechnology (SLINTEC)
AuthorAffiliation_xml – name: Sri Lanka Institute of Nanotechnology (SLINTEC)
– name: University of Cambridge
– name: Electrical Engineering Division, Department of Engineering
– name: University of Vienna
– name: Faculty of Physics
Author_xml – sequence: 1
  givenname: Dona T. L
  surname: Galhena
  fullname: Galhena, Dona T. L
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  givenname: Bernhard C
  surname: Bayer
  fullname: Bayer, Bernhard C
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  givenname: Stephan
  surname: Hofmann
  fullname: Hofmann, Stephan
– sequence: 4
  givenname: Gehan A. J
  surname: Amaratunga
  fullname: Amaratunga, Gehan A. J
  email: gaja1@cam.ac.uk
BackLink https://www.ncbi.nlm.nih.gov/pubmed/26714196$$D View this record in MEDLINE/PubMed
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Keywords in situ X-ray diffractometry
graphene oxide
interlayer constrictions
electrical double-layer capacitors
supercapacitors
subnanometer pores
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Title Understanding Capacitance Variation in Sub-nanometer Pores by in Situ Tuning of Interlayer Constrictions
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