Improved structural stability of titanium-doped β-[Bi.sub.2][O.sub.3] during visible-light-activated photocatalytic processes

• Published in: Journal of materials science Vol. 45; no. 5; pp. 1385 - 1392
• Main Authors: Wang, Yan, Wen, Yanyuan, Ding, Hanming, Shan, Yongkui
• Format: Journal Article
• Language: English
• Published: Springer 01.03.2010
• Subjects: Crystals; Diffraction; Oxides; Structure; Titanium; X-rays
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-009-4096-1

Due to its strong absorption to visible light and intrinsic polarizability, β-[Bi.sub.2][O.sub.3] could be a promising candidate for the visible-light-activated photocatalysis. However, its structural instability during a photocatalytic process prevents it from being used practically. In this work, titanium-doped β-[Bi.sub.2][O.sub.3] was synthesized by a hydrothermal method with subsequent calcination under 400 °C. Its crystal structure, photophysical property, and structural stability were investigated by using powder X-ray diffraction, Raman, infrared and diffuse reflectance UV-vis spectroscopies. The crystal structure of the titanium-doped β-[Bi.sub.2][O.sub.3] is analogous to β-[Bi.sub.2][O.sub.3]. These two oxides exhibited comparable photocatalytic activities on the photodegradation of indigo carmine, rhodamine B, and methylene blue under visible-light irradiation. However, unlike β-[Bi.sub.2][O.sub.3], the titanium-doped β-[Bi.sub.2][O.sub.3] was quite stable during these photocatalytic reactions. The improvement in structural stability was attributable to the substitution of titanium species in the host crystal lattice. The current investigation results point toward the possibility of metal ion-doped bismuth oxides as efficient visible-lightactivated photocatalysts.