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

Accepted version
Repository DOI

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

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.

electrical double-layer capacitors, graphene oxide, in situ X-ray diffractometry, interlayer constrictions, subnanometer pores, supercapacitors
Journal Title
ACS Nano
Conference Name
Journal ISSN
Volume Title
American Chemical Society (ACS)
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.