Rapid Preparation of Uniform High-Crystallized Mesoporous Titania Spheres without High-Temperature Treatment

Abstract

It is of such importance to prepare functional inorganic materials using a high-efficiency and low-cost strategy. In this work, uniform high-crystallized mesoporous titania (TiO 2 ) spheres are successfully synthesized via an advanced method. On the one hand, not only are the mesoporous anatase TiO 2 spheres well-crystallized without any high-temperature treatment but the total reaction time also can be largely shortened compared to the previous methods. On the other hand, the TiO 2 spheres still retain their high porosity and have a high specific surface area. Besides, the organic structure-directing agent can be cycled and used, being a representative of the rapid, effective, green, and low-cost methods. First, the systematical research studies are conducted by monitoring the formation process of the TiO 2 spheres in two kinds of reaction solutions using scanning electron microscopy, Xray diffraction, and energy-dispersive X-ray spectrum technologies. The results demonstrate that the mixed water/ethanol solution can be used to rapidly prepare the mesoporous TiO 2 spheres owing to the catalysis of water, compared to the single ethanol solution. Then, feasible mechanisms are proposed for the mesoporous TiO 2 spheres obtained in different solutions. Next, the preparation method is improved to avoid the appearance of separated nanoparticles, and thus, the uniform high-crystallized mesoporous TiO 2 spheres are successfully fabricated within only 4 h reaction time. Finally, the mesoporous TiO 2 spheres are employed as electrode materials and proved to be a promising anode of lithium-ion batteries.