Surfactant-free seed-mediated large-scale synthesis of mesoporous TiO₂ nanowires

We report low cost, high purity shape controlled strategies for the synthesis of mesporous 1D nanostructures owing to their diverse applications in photovoltaics, hydrogen production, and photocatalysis. A novel hydrothermal synthesis method is explored to produce surfactant-free seed mediated mesoporous TiO₂ nanowires in grams quantity. The effect of hydrothermal growth time on the evolution of the morphology and structural properties of mesoporous TiO₂ nanowires were systematically investigated. FESEM images showed that the diameter of these nanowires is in between 15 and 35 nm, and decreased with the growth time and their length is in few microns. The X-ray diffraction pattern and Raman vibrational spectra of annealed samples were corresponding to the anatase phase. A plausible orientation attachment driven growth was proposed to elucidate the formation mechanism of mesoporous TiO₂ nanowires.