Hydrothermal preparation of visible-light-activated photocatalyst Bi₁₂TiO₂₀ with different morphologies

Bi₁₂TiO₂₀ crystals with different morphologies are prepared by a hydrothermal process with no surfactants using Bi (NO₃)₃·5H₂O and Ti (OC₄H₉)₄. The morphologies and crystal structures are characterized by SEM and XRD. The results indicate that netlike and plate-like Bi₁₂TiO₂₀ crystals can be synthesized using KOH and NaOH, respectively, both belonging to the cubic crystal system. Furthermore, the photocatalysis properties are characterized by the photodegradation of RhB under simulated sunlight illumination. The results show that the two Bi₁₂TiO₂₀ samples synthesized by hydrothermal method have enhanced photocatalysis properties comparing with those synthesized by solid-state reaction under visible light irradiation. The photodegradation rate of RhB with plate-like Bi₁₂TiO₂₀ crystals can reach 78.2 % after 180 min of illumination.