title: Understanding Capacitance Variation in Sub-nanometer Pores by in Situ Tuning of Interlayer Constrictions.
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.
authors.affiliation: Electrical Engineering Division, Department of Engineering, University of Cambridge , 9 J. J. Thomson Avenue, CB3 0FA Cambridge, U.K.
authors.forename: Dona T L
authors.initials: DT
authors.lastname: Galhena
authors.affiliation: Electrical Engineering Division, Department of Engineering, University of Cambridge , 9 J. J. Thomson Avenue, CB3 0FA Cambridge, U.K.|Faculty of Physics, University of Vienna , Boltzmanngasse 5, A 1090 Vienna, Austria.
authors.forename: Bernhard C
authors.initials: BC
authors.lastname: Bayer
authors.affiliation: Electrical Engineering Division, Department of Engineering, University of Cambridge , 9 J. J. Thomson Avenue, CB3 0FA Cambridge, U.K.
authors.forename: Stephan
authors.initials: S
authors.lastname: Hofmann
authors.affiliation: Electrical Engineering Division, Department of Engineering, University of Cambridge , 9 J. J. Thomson Avenue, CB3 0FA Cambridge, U.K.|Sri Lanka Institute of Nanotechnology (SLINTEC) , Pitipana, Homagama, Sri Lanka.
authors.forename: Gehan A J
authors.initials: GA
authors.lastname: Amaratunga
keywords: electrical double-layer capacitors; graphene oxide; in situ X-ray diffractometry; interlayer constrictions; subnanometer pores; supercapacitors