(a)
(b)
(c)
(d)
Figure 8: TEM images of (a) anatase nanoparticles aggregates from (b) FG-ref and (c) E-3 sample, decorated with the amorphous surface layer (indicated by arrows). (d) The elemental map of the anatase nanoparticle reveals the enrichment of surface layers by Si (Si: green, Ti: red).