Figure 2: Physical characterisation of the Ge-QD@NG/NGF.

(a,b) Photographs of a flexible Ge-QD@NG/NGF yolk-shell electrode (7 × 4 cm). (c) SEM image of the Ge-QD@NG/NGF yolk-shell nanoarchitecture. (d) EDS elemental maps of Ge, C and N, respectively. (e) TEM image of the Ge-QD@NG/NGF yolk-shell nanoarchitecture. (f) High-resolution TEM of the Ge-QD@NG/NGF yolk-shell nanoarchitecture. (g) The electronic diffraction pattern corresponding to the Ge-QD. (h) XRD patterns and (i) Raman spectra of the Ge-QD@NG/NGF yolk-shell nanoarchitecture and NGF.