Effects of ytterbium on potassium titanate for enhanced photocatalytic degradation of Acid red 1

A sol–gel method was used to prepare Yb_n-K₂Ti₆O₁₃ to show ytterbium’s effects on potassium titanate’s properties. The crystallite sizes of monoclinic K₂Ti₆O₁₃ phase for K₂Ti₆O₁₃, Yb_0.15-K₂Ti₆O₁₃ and Yb_0.3-K₂Ti₆O₁₃ were calculated to be 25.5, 44.9 and 41.1 nm. The specific surface area and pore volume of K₂Ti₆O₁₃ were small, and Yb_0.15-K₂Ti₆O₁₃ had the largest specific surface area (9.10 m²/g) and pore volume (0.0193 cm³/g). The photoluminescence intensity reduced in the sequence: K₂Ti₆O₁₃, Yb_0.3-K₂Ti₆O₁₃ and Yb_0.15-K₂Ti₆O₁₃. The photocatalytic activities of Yb_n-K₂Ti₆O₁₃ were much better than that of K₂Ti₆O₁₃, and the degradation efficiencies in 80 min for Yb_0.15-K₂Ti₆O₁₃, Yb_0.3-K₂Ti₆O₁₃ and K₂Ti₆O₁₃ were determined to be 89.6%, 69.9% and 56.3%. The 600 mg/L dosage of Yb_0.15-K₂Ti₆O₁₃ was suitable for the photocatalytic reaction.