Retraction notice to “Influence of Pr3+ doping on the synthesis of colloidal sols and nanoparticulate TiO2 xerogels and their photocatalytic activity” [Materials Characterization, Vol 182 (2021) 111536] (Materials Characterization (2021) 182, (S1044580321006586), (10.1016/j.matchar.2021.111536))

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editors-in-Chief. The authors have reused images that are part of the following paper authored by Mario Borlaf, Rodrigo Moreno, Angel L. Ortiz and María T. Colomer: Synthesis and photocatalytic activity of Eu3 + −doped nanoparticulate TiO2 sols and thermal stability of the resulting xerogels with doi https://doi.org/10.1016/j.matchemphys.2013.11.058. Figs. 1 and 3 are both duplicated and claimed to be from a different composition than was used in the previous MatChemPhys paper. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited and the standards of Materials Characterization require that this manuscript be retracted. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.