Journal Article

PUBDB-2025-04471

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png X‐Ray Absorption Spectroscopy Probing of Gold Electro‐Oxidation Reveals Intermediate Surficial Au(I)

Degerman, D. (Corresponding author)Extern* ; Boscolo Bibi, S.Extern* ; Davies, B.Extern* ; Grigorev, V.Extern* ; Kalinko, A.DESY* ; Hansson, T.Extern*XFEL.EU* ; Koroidov, S. (Corresponding author)Extern*

2025
Wiley-VCH Weinheim

This record in other databases:    

Please use a persistent id in citations: doi:10.1002/celc.202500127  doi:10.3204/PUBDB-2025-04471

Abstract: While Au electro-oxidation in acidic aqueous media on a phenomenological level proceeds directly from Au(0) to Au(III), it has previously been suggested that Au(I) states are intermediate species of the oxidation mechanism. Here, additional evidence for the transient Au(I) is provided by the probing the electro-oxidation of Au electrode operando in a pH = 3 perchloric acid (HClO$_4$) electrolyte by high-energy-resolution fluorescence-detected X-ray absorption near-edge structure (HERFD–XANES) at potentials up to 1.8 V versus the reversible hydrogen electrode (RHE). The perchlorate ions (ClO$_4$−) in the electrolyte are used as sacrificial oxidizing agents. The reduced perchlorate compounds in turn produce chloride ions, which react with Au ions to form Au–Cl compounds. The operando HERFD–XANES detects and identifies the chlorinated compounds as surficial Au(I), present during the early stages of Au oxidation. It is further inferred that Au(I) is accessed by the electrolyte. These observations are consistent with the previously hypothesized route for Au electro-oxidation involving charge transfer after a dipole-induced place-exchange step.

---

Contributing Institute(s):

1. DOOR-User (DOOR ; HAS-User)
2. Experimentebetreuung PETRA III (FS-PET-S)

Research Program(s):

1. 632 - Materials – Quantum, Complex and Functional Materials (POF4-632) (POF4-632)
2. 6G3 - PETRA III (DESY) (POF4-6G3) (POF4-6G3)
3. SWEDEN-DESY - SWEDEN-DESY Collaboration (2020_Join2-SWEDEN-DESY) (2020_Join2-SWEDEN-DESY)
4. FS-Proposal: I-20190137 EC (I-20190137-EC) (I-20190137-EC)

Experiment(s):

1. PETRA Beamline P64 (PETRA III)

Appears in the scientific report 2025

---

Database coverage:
; ; ; ; Article Processing Charges ; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; DEAL Wiley ; DOAJ Seal ; Essential Science Indicators ; Fees ; IF < 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---