Synthesis of TiO2 hollow spheres using binary ionic liquids as an electrocatalyst

Titanium dioxide (TiO₂ titania) hollow sphere was simply synthesized using various ionic liquids (ILs). The shape and size of TiO₂ particles were significantly different with the composition of ILs. This is mainly attributed to the interaction between organic solvent and IL at the interface leading to the formation of sphere. Among the binary ILs, Bmim]BF₄] + Omim]PF₆], Bmim]BF₄] + Omim]PF₆], and Bmim]PF₆] + Hmim]PF₆] were useful to prepare TiO₂ nanostructures with high surface area and anatase phase. Especially, Bmim]BF₄] + Omim]PF₆] was the most effective IL to synthesize an anatase TiO₂ hollow sphere.