Publications Repository - Gdańsk University of Technology

A series of Er3+-TiO2, Yb3+-TiO2 and Er3+/Yb3+-TiO2 photocatalysts were obtained via sol-gel method, using rare earth metal (RE) precursor ranging from 0.25 to 10 mol%. The experiments demonstrated that phenol in aqueous solutions was successfully degraded under visible light (> 450 nm) using RE3+-TiO2. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron emission spectroscopy (XPS), UV-Vis absorption measurement, BET surface area analysis and luminescent spectroscopy. XPS analysis revealed that erbium and ytterbium were present in the form of oxides. The sample showing the highest photoactivity was in the form of anatase, its surface area equaled to 125 m2/g, average crystals size was 13 nm and contained 1 mol% of Yb3+. 3 h of irradiation resulted in 89 % of phenol degradation under visible light. For TiO2 materials doped with Er3+ or Yb3+/Er3+ after excitation by 978 nm laser beam, low intensive up-conversion emission was observed. Action spectra analysis of Er/Yb-TiO2 revealed that irradiation from range 420 to 475 nm is responsible for visible light photocatalytic activity.

Authors

• mgr inż. Joanna Reszczyńska link open in new tab ,
• Tomasz Grzyb,
• Janusz W. Sobczak,
• Wojciech Lisowski,
• prof. dr hab. inż. Maria Gazda link open in new tab ,
• Bunsho Ohtani,
• prof. dr hab. inż. Adriana Zaleska-Medynska link open in new tab