3D hierarchical flower-like TiO2 nanostructure: morphology control and its photocatalytic property

3D hierarchical flower-like TiO2 nanostructures were synthesized via a facile solvothermal method combining a calcination process. A series of electron microscopy characterization results suggest that the growth of 3D hierarchical flower-like TiO2 nanostructures is governed by a nucleation and nuclei growth-dissolution-recrystallization growth mechanism from time-dependent morphology evolution. The influence of the experimental parameters such as reaction species, temperature, and time on the morphology growth was systematically studied. Importantly, the prepared 3D hierarchical flower-like TiO2 nanostructures showed enhanced photocatalytic activity compared with Degussa P25 for the degradation of phenol under UV light irradiation, which is attributed to its special hierarchical porous structure, good permeability, high light-harvesting capacity and more surface active sites. Electron spin resonance (ESR) detection of active oxygen species (hydroxyl radicals) and the total organic carbon (TOC) changes are also investigated to evaluate the degradation efficacy.