Photocatalytic Properties of Nanotubular-Shaped TiO_𝟐 Powders with Anatase Phase Obtained from Titanate Nanotube Powder through Various Thermal Treatments

Figure 4

Scanning electron microscopy images of the calcined powders at 475°C for (a) 10 min, (b) 60 min, (c) 120 min, and (d) 240 min in O₂ atmosphere.

(a)

(b)

(c)

(d)