Retraction Note to: J Mater Sci: Mater Electron (2019) 30:9281–9288. https://doi.org/10.1007/s10854-019-01258-4

The Editor-in-Chief has retracted this article. After publication, concerns were raised about repeated features among the different panels in Fig. 2, as well as between Fig. 2 in this article and Fig. 2 in another article from one of the corresponding authors [1]. 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.