TY - JOUR

T1 - Towards Real-Time Ion-Specific Structural Sensitivity in Nanoporous Carbon Electrodes Using in Situ Anomalous Small-Angle X-ray Scattering

AU - Koczwara, Christian

AU - Prehal, Christian

AU - Haas, Sylvio

AU - Boesecke, Peter

AU - Huesing, Nicola

AU - Paris, Oskar

PY - 2019/11/13

Y1 - 2019/11/13

N2 - 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.

AB - 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.

KW - anomalous small-angle X-ray scattering

KW - EDLC

KW - in situ

KW - ion-specific

KW - structural sensitivity

KW - supercapacitor

UR - http://www.scopus.com/inward/record.url?scp=85074815323&partnerID=8YFLogxK

U2 - 10.1021/acsami.9b14242

DO - 10.1021/acsami.9b14242

M3 - Article

C2 - 31633905

AN - SCOPUS:85074815323

VL - 11.2019

SP - 42214

EP - 42220

JO - ACS Applied Materials and Interfaces

JF - ACS Applied Materials and Interfaces

SN - 1944-8244

IS - 45

ER -