Figure 2

SEM images of (a) PAN/PVP-7/3 (b) PAN/PVP-6/4 (c) PAN/PVP-5/5 (d) PVP (214) (e) PVP (333) (f) PVP (500) samples, Inserts are magnified images; (g,h) TEM images of PVP (333) sample; (i) physical photo of PAN/PVP-6/4 sample, Insert is the physical photo of PVP (333) sample.