Conflict of Interest The authors declare no conflict of interest. Data Availability Statement The authors confirm that the data supporting the findings of this study are available within the article and its Electronic Supplementary Information (ESI). Additional SEM and TEM images, N2 adsorption-desorption isotherms, supplementary XPS spectra of Fe, Mg, and Ni (including survey spectra), and UV-Vis spectra are provided in the ESI.