Lanthanide Oxide Doped Titanium Dioxide Photocatalysts: Effective Photocatalysts for the Enhanced Degradation of Salicylic Acid and t-Cinnamic Acid

• Published in: Journal of catalysis Vol. 204; no. 2; pp. 305 - 313
• Main Authors: Ranjit, K.T, Willner, I, Bossmann, S.H, Braun, A.M
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 10-12-2001; Elsevier
• Subjects: adsorption; Chemistry; doped titanium dioxide; Exact sciences and technology; General and physical chemistry; lanthanide oxide; photocatalyst; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); salicylic acid; t-cinnamic acid; doped titanium dioxide; t-cinnamic acid; adsorption; salicylic acid; lanthanide oxide; photocatalyst; Salicylic acid; Binary compound; Europium Oxides; Transition metal Compounds; Cinnamic acid; Photocatalysis; Adsorption isotherm; Praseodymium Oxides; Ytterbium Oxides; Degradation; Carboxylic acid; Phenols; Benzenic compound; Lanthanide Compounds; Titanium oxide
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1006/jcat.2001.3388

The photocatalytic degradation of salicylic acid and t-cinnamic acid has been investigated in aqueous suspensions of lanthanide oxide doped TiO2 photocatalysts. Complete mineralization has been achieved in the case of lanthanide oxide doped TiO2 photocatalysts in total contrast to the formation of intermediates in case of nonmodified TiO2. The equilibrium dark adsorption of salicylic acid and t-cinnamic acid is ca. three times and two times higher, respectively, on the lanthanide oxide modified catalysts as compared to the nonmodified TiO2 catalyst. The adsorption isotherms were analyzed in terms of the Langmuir theory and a good fit was obtained. The enhanced degradation is attributed to the formation of the Lewis acid–base complex between the lanthanide ion and the substrates at the photocatalyst surface. The concentration of the organic acids at the composite Ln2O3/TiO2 photocatalysts could provide a means for the enhanced activity.