Free-Standing Porous Carbon Nanofiber Networks from Electrospinning Polyimide for Supercapacitors

Figure 2

The SEM images of (a) PAA-SiO₂ fibers, (b) CFN-SiO₂ fibers, and (d) porous CFNs and (c) the energy spectra of CFN-SiO₂ fibers.

(a)

(b)

(c)

(d)