Time‐resolved X‐ray absorption spectroelectrochemistry of redox active species in solution

• Published in: Journal of synchrotron radiation Vol. 26; no. 6; pp. 1980 - 1985
• Main Authors: Cheaib, Khaled, Maurice, Baptiste, Mateo, Tiphaine, Halime, Zakaria, Lassalle-Kaiser, Benedikt
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.11.2019; John Wiley & Sons, Inc
• Subjects: Absorption spectra; Analytical chemistry; Chemical Sciences; Conversion; cyclic voltammetry; Electrochemistry; Inorganic chemistry; Organic chemistry; redox reactions; Scanning; Spectrum analysis; time‐resolved X‐ray absorption spectroscopy; Voltammetry
• ISSN: 1600-5775; 0909-0495; 1600-5775
• DOI: 10.1107/S1600577519013614

Electrochemistry and electrocatalysis have been receiving increased attention recently due to their crucial contribution to electrical‐to‐chemical conversion systems. We describe here the development and operation of a new spectroelectrochemical transmission cell for time‐resolved X‐ray absorption spectroscopy of solutions. X‐ray absorption spectra were recorded on the ROCK beamline of SOLEIL under constant and scanning potentials. Spectra were recorded at a frequency of 2 Hz during a cyclic voltammetry experiment performed on a 20 mM solution of FeIIICl3·6H2O at 20 mV s−1 scanning speed. Spectra with good signal‐to‐noise ratios were obtained when averaging ten spectra over 5 s, corresponding to a 100 mV potential range. A 90% conversion rate from Fe(III) to Fe(II) was spectroscopically demonstrated in cyclic voltammetry mode. X‐ray absorption spectra can be recorded at different points in time during a cyclic voltammetry experiment. This time‐resolved X‐ray spectroelectrochemistry technique can be used to probe transient species formed at an electrode in solution.