Fig. 2

Morphology of PANS via transmission electron microscopic (TEM, left) and scanning electron microscopic (SEM, right) imaging. Alphabetic characters represent sequential synthetic processes of PANS; (E): extracting reactant with BE, (H): heating sequentially the reactant at 200 °C and 300 °C, and (S): swelling the reactant using EtOH. Note that (X): no treatment. Scale bars are 500 nm