Retraction Note: Air-stable superparamagnetic metal nanoparticles entrapped in graphene oxide matrix.

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1038/s41467-020-19968-3.

Retraction of: Nature Communications 10.1038/ncomms12879, published online 15 September 2016.

The authors are retracting this Article because two figures with Mössbauer spectra have raised concerns. For Supplementary Fig. 6 and related discussion on the stability of the superparamagnetic iron nanoparticles, we no longer had the raw data and are thus unable to verify the claims in the published paper. Additionally, due to very low Mössbauer effect of superparamagnetic iron nanoparticles embedded in graphene oxide matrix and related low statistical quality of raw Mössbauer data, there is uncertainty in values of Mössbauer parameters derived from Figure 2, and we, the authors, therefore wish to retract this Article.