Time-Resolved Study of the Oxidation of Ethanol by Cerium(IV) Using Combined Quick-XANES, UV−Vis, and Raman Spectroscopies

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 109; no. 2; pp. 320 - 329
• Main Authors: Briois, V, Lützenkirchen-Hecht, D, Villain, F, Fonda, E, Belin, S, Griesebock, B, Frahm, R
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.01.2005
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp046691t

Time-resolved X-ray absorption spectroscopy (Quick-XANES) has been combined with UV−vis and Raman spectroscopies to study the in situ reduction of Ce4+ to Ce3+ in ethanolic solution with a time resolution of ca. 4−5 s. For this purpose, a cam-driven oscillating double-crystal monochromator with a channel-cut crystal was combined with two spectrometers for UV−vis and Raman spectroscopies in a specialized cell which allows one to fit the optical pathways for all three spectroscopies individually. The results show that high-quality results can be obtained simultaneously, thus giving a detailed insight into the mechanisms of the investigated chemical reaction. The continuous release of nitrate and ethanol ligands from the initial Ce4+ into the solution finally leads to a trivalent cerium species which is only coordinated with water molecules after about 1800 s of reaction time.