Towards Real-Time Ion-Specific Structural Sensitivity in Nanoporous Carbon Electrodes Using in Situ Anomalous Small-Angle X-ray Scattering

Christian Koczwara, Christian Prehal, Sylvio Haas, Peter Boesecke, Nicola Huesing, Oskar Paris*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Current in situ techniques to study ion charge storage and electrical double-layer formation in nanoporous electrodes are either chemically sensitive to element-specific concentration changes or structurally sensitive to rearrangements of ions and solvent molecules; but rarely can they cover both. Here we introduce in situ anomalous small-angle X-ray scattering (ASAXS) as a unique method to extract both real-time structural and ion-specific chemical information from one single experiment. Using a 1 M RbBr aqueous electrolyte and a hierarchical micro- and mesoporous carbon electrode, we identify different charging mechanisms for positive and negative applied potentials. We are able not only to track the global concentration change of each ion species individually, but also to observe their individual local rearrangement within the pore space.

Original languageEnglish
JournalACS Applied Materials and Interfaces
Publication statusPublished - 1 Jan 2019


  • anomalous small-angle X-ray scattering
  • EDLC
  • in situ
  • ion-specific
  • structural sensitivity
  • supercapacitor

ASJC Scopus subject areas

  • Materials Science(all)

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