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Title: Open-source electrochemical cell for in situ X-ray absorption spectroscopy in transmission and fluorescence modes
X-ray spectroscopy is a valuable technique for the study of many materials systems. Characterizing reactionsin situandoperandocan reveal complex reaction kinetics, which is crucial to understanding active site composition and reaction mechanisms. In this project, the design, fabrication and testing of an open-source and easy-to-fabricate electrochemical cell forin situelectrochemistry compatible with X-ray absorption spectroscopy in both transmission and fluorescence modes are accomplished via windows with large opening angles on both the upstream and downstream sides of the cell. Using a hobbyist computer numerical control machine and free 3D CAD software, anyone can make a reliable electrochemical cell using this design. Onion-like carbon nanoparticles, with a 1:3 iron-to-cobalt ratio, were drop-coated onto carbon paper for testingin situX-ray absorption spectroscopy. Cyclic voltammetry of the carbon paper showed the expected behavior, with no increased ohmic drop, even in sandwiched cells. Chronoamperometry was used to apply 0.4 V versus reversible hydrogen electrode, with and without 15 min of oxygen purging to ensure that the electrochemical cell does not provide any artefacts due to gas purging. The XANES and EXAFS spectra showed no differences with and without oxygen, as expected at 0.4 V, without any artefacts due to gas purging. The development of this open-source electrochemical cell design allows for improved collection ofin situX-ray absorption spectroscopy data and enables researchers to perform both transmission and fluorescence simultaneously. It additionally addresses key practical considerations including gas purging, reduced ionic resistance and leak prevention.  more » « less
Award ID(s):
1827622
PAR ID:
10513807
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
International Union of Crystallography
Date Published:
Journal Name:
Journal of Synchrotron Radiation
Volume:
31
Issue:
2
ISSN:
1600-5775
Page Range / eLocation ID:
322 to 327
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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