Aerosol-assisted processing of hierarchically organised TiO_{2 nanoparticles

Hierarchically assembled TiO2 nanoparticles into larger spherical ones were obtained using aerosol–assisted processing method. Unagglomerated particles with the mean size of 440 nm were obtained from colloidal solution of TiO2 nanoparticles (~4.5 nm) using ultrasonic spray pyrolysis at 550°C. Their morphological complexity and structural polymorphism were investigated by using X–ray powder diffraction (XRPD), scanning electron microscopy (SEM), energy dispersive X–ray spectroscopy (EDS) and transmission electron microscopy (TEM) coupled with selected area electron diffraction (SAED) analysis. Pronounced evolution of nanocrystalline TiO2(B) phase assembled together with the anatase building units (sized ~15 nm) in uniform submicrometric particles implicate their feasibility to be used in dye–sensitised solar cells and lithium ion batteries.