Repository logo
 

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

Accepted version
Peer-reviewed

Repository DOI


Type

Article

Change log

Authors

Galhena, Dona TL 
Bayer, Bernhard C 
Amaratunga, Gehan AJ 

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.

Description

Keywords

electrical double-layer capacitors, graphene oxide, in situ X-ray diffractometry, interlayer constrictions, subnanometer pores, supercapacitors

Journal Title

ACS Nano

Conference Name

Journal ISSN

1936-0851
1936-086X

Volume Title

10

Publisher

American Chemical Society (ACS)
Sponsorship
DTLG acknowledges technical support by J. N. R. Grundy (University of Cambridge) and financial support from Newnham College, Cambridge and the Cambridge Commonwealth Trust. GAJA acknowledges partial support for this work from Dyson Ltd. BCB acknowledges a College Research Fellowship at Hughes Hall, Cambridge. DTLG and GAJA thank Ananda Hettiarachchy and K. M. N. de Silva for discussions on activated carbon.