Figure 2. Reduction of the CMG networks.

(a) XPS analysis of the networks before and after reduction. The XPS C1 signals were fitted to five components: C=C and C–C, C–O, C=O and COOR for the as-prepared ice template CMG network and C=C, C=O and C–O, and COOR and the π–π shake up for the reduced CMG network. The rCMG atomic composition is C1s (79.1%), N1s (0.5%), O1s(12.0%), Si2p (7.6%), Mn2p (0.6%), Na1s (0.3%). Silicon and Nitrogen are attributed to the vacuum grease used during the freeze casting process while the small fraction of Manganese could be a residue from the synthesis route. (b) Corresponding Raman analysis. Thermal reduction results in sharper D and G peaks and, the appearance of the 2D peak at 2,700 cm⁻¹ which is characteristic of graphene.