Visible Light Excited Catalysis and Reusability Performances of TiO₂@Pr:Y₂SiO₅ Upconversion Materials

Figure 3

SEM photos of samples. (a) GFF; (b) TiO₂@GFF; (c) TPY@GFF; and (d) TPY@GFF used 6 times.

(a)

(b)

(c)

(d)