Retraction notice to “Improved mixed-dimensional 3D/2D perovskite layer with formamidinium bromide salt for highly efficient and stable perovskite solar cells” [Chem. Eng. J. 428 (2022) 131185] (Chemical Engineering Journal (2022) 428, (S1385894721027662), (10.1016/j.cej.2021.131185))

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Executive Editor due to concerns about the integrity of the research reported. Concerns were raised about the reliability of the data presented in Figure 4A and 4C (detailed on Pubpeer), whereby unexpected similarities were observed in the noise features of the XRD spectra of different experimental samples. The authors were contacted for comment about the above-mentioned concerns but were unable to provide a suitable explanation for how the similarities came about. The Editor has therefore lost confidence in the reliability of the findings presented in this article as a whole. In light of the above, the Editor believes that the most responsible course of action is to retract the paper. Apologies are offered to the readers that this was not detected sooner.