Preparation of Porous F-WO₃/TiO₂ Films with Visible-Light Photocatalytic Activity by Microarc Oxidation

Figure 3

High resolution XPS spectrum of: (a) Ti2p, (b) O1s, (c) W4f/Wd, and (d) F1s core levels of the mTiO₂ film.

(a)

(b)

(c)

(d)