2 was synthesized by the gaseous-liquid detonation (GLD) method using H2, O2, and TiCl4 as the mixture precursors. The effects of different molar ratios of precursors and initial reaction pressures on the nano-TiO2 crystalline structures were studied. The nanocrystal structures, components, particle size, and morphology were characterized by the X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results demonstrate that the nano-TiO2 consists of pure anatase-TiO2, pure rutile-TiO2, and the mixtures of spherical or quasi-spherical morphologies with particle size of 20~150 nm. Furthermore, the formation mechanism of nano-TiO2 by GLD method was analyzed. The relevant GLD parameters were calculated based on the C-J theory and the related chemical reaction data, which effectively verifies the influence of different molar ratios of precursors and initial pressures on the controllable synthesis of polycrystalline nano-TiO2."/>
2;gaseous-liquid detonation;polycrystalline nanostructure;detonation parameters;C-J theory"/>