1 Retraction Note to: Journal of Materials Science: Materials in Electronics (2019) 30:7018–7030 https://doi.org/10.1007/s10854-019-01019-3

The Editor-in-chief has retracted this article. After publication, concerns were raised about repeated features in images representing different samples in Figs. 2 and 8. The Editor-in-Chief therefore no longer has confidence in the integrity of the data in this article.

None of the authors have responded to any correspondence from the editor or publisher about this retraction notice.