Multi-spectroscopic study of electrochemically-formed oxide-derived gold electrodesShow others and affiliations
2024 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 26, no 3, p. 2332-2340Article in journal (Refereed) Published
Abstract [en]
Oxide-derived metals are produced by reducing an oxide precursor. These materials, including gold, have shown improved catalytic performance over many native metals. The origin of this improvement for gold is not yet understood. In this study, operando non-resonant sum frequency generation (SFG) and ex situ high-pressure X-ray photoelectron spectroscopy (HP-XPS) have been employed to investigate electrochemically-formed oxide-derived gold (OD-Au) from polycrystalline gold surfaces. A range of different oxidizing conditions were used to form OD-Au in acidic aqueous medium (H3PO4, pH = 1). Our electrochemical data after OD-Au is generated suggest that the surface is metallic gold, however SFG signal variations indicate the presence of subsurface gold oxide remnants between the metallic gold surface layer and bulk gold. The HP-XPS results suggest that this subsurface gold oxide could be in the form of Au2O3 or Au(OH)3. Furthermore, the SFG measurements show that with reducing electrochemical treatments the original gold metallic state can be restored, meaning the subsurface gold oxide is released. This work demonstrates that remnants of gold oxide persist beneath the topmost gold layer when the OD-Au is created, potentially facilitating the understanding of the improved catalytic properties of OD-Au.
Place, publisher, year, edition, pages
Royal Society of Chemistry, 2024. Vol. 26, no 3, p. 2332-2340
National Category
Other Chemistry Topics
Identifiers
URN: urn:nbn:se:liu:diva-201287DOI: 10.1039/d3cp04009gISI: 001134636400001PubMedID: 38165839Scopus ID: 2-s2.0-85181438734OAI: oai:DiVA.org:liu-201287DiVA, id: diva2:1842147
Funder
Swedish Research Council, 2019-05114Knut and Alice Wallenberg Foundation, 2016.00422024-03-032024-03-032025-01-30Bibliographically approved