XPS study of zinc hydroxide as a potential corrosion product of zinc: Rapid X-ray induced conversion into zinc oxide

Highlights: • Zn(OH)2 is studied in detail by means of the X-ray photoelectron spectroscopy. • Zn(OH)2 rapidly decomposes to ZnO during the standard XPS measurement. • Formed ZnO critically complicates the identification of Zn(OH)2. • The decomposition is driven by X-ray radiation and cannot be suppressed totally. • Sample cooling and short spectra acquisition time minimize its negative impact. - Abstract: A detailed investigation of a potential corrosion product of zinc – zinc hydroxide – using X-ray photoelectron spectroscopy (XPS) was performed to shed light on remarkable inconsistencies in the literature reported reference data, being the key element for the evaluation of the unknown experimental spectra. Our study gives an explanation, showing that zinc hydroxide possesses a highly unstable nature resulting in rapid degradation and leading to the formation of zinc oxide during standard XPS measurements. Furthermore, a probable mechanism of the observed phenomenon, X-ray induced material degradation, is proposed and discussed