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

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Sylvio Haas
  • Peter Boesecke
  • Nicola Huesing

Organisational units

External Organisational units

  • Technische Universität Graz
  • Photon Science, Deutsches Elektronen-Synchrotron DESY, Hamburg,
  • ESRF
  • SMBS - University of Salzburg Business School, Sigmund-Haffner-Gasse 18, A-5020 Salzburg, Austria

Abstract

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.

Details

Original languageEnglish
Pages (from-to)42214-42220
Number of pages7
JournalACS Applied Materials and Interfaces
Volume11.2019
Issue number45
DOIs
Publication statusPublished - 13 Nov 2019