Print Email Facebook Twitter Operando EXAFS study reveals presence of oxygen in oxide-derived silver catalysts for electrochemical CO2 reduction Title Operando EXAFS study reveals presence of oxygen in oxide-derived silver catalysts for electrochemical CO2 reduction Author Firet, N.J. (TU Delft ChemE/Materials for Energy Conversion and Storage) Blommaert, M.A. (TU Delft ChemE/Materials for Energy Conversion and Storage) Burdyny, T.E. (TU Delft ChemE/Materials for Energy Conversion and Storage) Venugopal, A. (TU Delft ChemE/Materials for Energy Conversion and Storage) Bohra, D. (TU Delft ChemE/Materials for Energy Conversion and Storage) Longo, Alessandro (European Synchrotron Radiation Facility; Instituto per lo Studio dei Materiali Nanostrutturati) Smith, W.A. (TU Delft ChemE/Materials for Energy Conversion and Storage) Date 2019 Abstract Electrocatalysis of carbon dioxide can provide a valuable pathway towards the sustainable production of chemicals and fuels from renewable electricity sources. One of the main challenges to enable this technology is to find suitable electrodes that can act as efficient, stable and selective CO2 reduction catalysts. Modified silver catalysts and in particular, catalysts electrochemically derived from silver-oxides, have shown great promise in this regard. Here, we use operando EXAFS analysis to study the differences in surface composition between a pure silver film and oxide-derived silver catalysts-a nanostructured catalyst with improved CO2 reduction performance. The EXAFS analysis reveals the presence of trace amounts of oxygen in the oxide-derived silver samples, with the measured oxygen content correlating well with experimental studies showing an increase in CO2 reduction reactivity towards carbon monoxide. The selectivity towards CO production also partially scales with the increased surface area, showing that the morphology, local composition and electronic structure all play important roles in the improved activity and selectivity of oxide-derived silver electrocatalysts. Earlier studies based on X-ray photoelectron spectroscopy (XPS) were not able to identify this oxygen, most likely because in ultra-high vacuum conditions, silver can self-reduce to Ag0, removing existing oxygen species. This operando EXAFS study shows the potential for in situ and operando techniques to probe catalyst surfaces during electrolysis and aid in the overall understanding of electrochemical systems. To reference this document use: http://resolver.tudelft.nl/uuid:0d71cf64-db3e-49be-a813-8544fed6fc30 DOI https://doi.org/10.1039/c8ta10412c ISSN 2050-7488 Source Journal of Materials Chemistry A, 7 (6), 2597-2607 Bibliographical note Accepted Author Manuscript Part of collection Institutional Repository Document type journal article Rights © 2019 N.J. Firet, M.A. Blommaert, T.E. Burdyny, A. Venugopal, D. Bohra, Alessandro Longo, W.A. Smith Files PDF c8ta10412c.pdf 1.14 MB Close viewer /islandora/object/uuid:0d71cf64-db3e-49be-a813-8544fed6fc30/datastream/OBJ/view