Sol-gel synthesis of TiO2 (anatase) and TiO2(B) was carried out in the presence of imidazolium based ionic liquids with tetrafluoroborate and chloride ions. The prepared nanoparticles were characterized by cyclic voltammetry, Raman spectroscopy and scanning electron microscopy. The influence of organic solvent type and synthesis atmosphere on the product's composition was evaluated. It was established that a nitrogen atmosphere favours the growth of anatase crystalline phase and inhibits the formation of TiO2(B). (C) 2014 Elsevier B.V. All rights reserved.