XPS quantification of oxygen vacancies in mesoporous and non-mesoporous CeO2: comment on an article by Thill et al., J. Mater. Chem. A, 2020, 8, 24752–24762

The present Comment emphasises that accurate speciation of the chemistry of the cerium in the authors' catalysts requires careful consideration of the line shape of XPS Ce 3d spectra characteristic of CeO 2 and Ce 2 O 3 oxides.