Publications Repository - Gdańsk University of Technology

Because of the tremendous structural diversityof ionic liquids (ILs), simple transfer of observations performed for one IL used for IL-TiO2 preparation on different samples is not possible. Therefore, four ionic liquids, all containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, ammonium, imidazolium), were used for the first time for the preparation of IL-TiO2 composites. The role of the individual IL cation in the synthesis of TiO2 microspheres, as well as the effect of the IL structure on the mechanism of the visible-light (Vis)-induced photoactivity of IL-TiO2 was presented and discussed in regard to structure, morphology, absorption properties, elemental composition, and reactive species involved in the photocatalytic reaction of phenol degradation. The successful modification of the TiO2 with organic IL species including possible interactions between IL and TiO2 surface, as well as the TiO2 matrix (doping with N), were confirmed. The sample that exhibited the highest photoactivity under Vis irradiation (58%) was TiO2 prepared in a presence of 1-butylpyridinium chloride with a IL:precursor molar ratio of 1:3. For this sample, the highest partial decomposition of cationic species of IL was observed resulting in interaction of N atoms with deeper sites of TiO2 (Ti-Nx) as well as the highest surface defects in a form of Ti3+. The superoxide radical species O2• − were found to be main active species responsible for high efficiency of degradation under Vis irradiation.

Authors

• dr inż. Marta Paszkiewicz-Gawron,
• Marta Długokęcka link open in new tab ,
• dr hab. Wojciech Lisowski,
• Maria Paganini,
• Elio Giamello,
• prof. dr hab. inż. Tomasz Klimczuk link open in new tab ,
• Monika Paszkiewicz,
• Ewelina Grabowska,
• Prof. dr hab. inż. Adriana Zaleska-Medynska,
• dr hab. inż. Justyna Łuczak link open in new tab