CNR-Istituto di Scienze e Tecnologie Molecolari, Via Golgi 19, 20133 Milano, Italy.
Ultrason Sonochem. 2013 Jan;20(1):445-51. doi: 10.1016/j.ultsonch.2012.07.003. Epub 2012 Jul 20.
The synthesis of highly-crystalline porous TiO(2) microspheres is reported using ultrasonic spray pyrolysis (USP) in the presence of colloidal silica as a template. We have exploited the interactions between hot SiO(2) template particles surface and TiO(2) precursor that occur during reaction inside the droplets, to control the physical and chemical properties of the resulting particles. Varying the SiO(2) to titanium precursor molar ratio and the colloidal silica dimension, we obtained porous titania microspheres with tunable morphology, porosity, BET surface area, crystallite size, band-gap, and phase composition. In this regard, we have also observed the preferential formation of anatase vs. rutile with increasing initial surface area of the silica template. The porous TiO(2) microspheres were tested in the photocatalytic degradation of nitrogen oxides (NO(x)) in the gas phase. USP prepared nanostructured titania samples were found to have significantly superior specific activity per surface area compared to a commercial reference sample (P25 by Evonik-Degussa).
本文采用超声喷雾热解法（USP），在胶体二氧化硅存在的情况下，成功制备了高结晶度多孔 TiO(2) 微球。我们利用了在液滴内反应过程中，SiO(2) 模板粒子表面与 TiO(2) 前驱体之间的相互作用，来控制所得粒子的物理化学性质。通过改变 SiO(2)与钛前驱体的摩尔比和胶体二氧化硅的尺寸，我们获得了具有可调形态、孔隙率、BET 比表面积、晶粒尺寸、带隙和相组成的多孔 TiO(2) 微球。在这方面，我们还观察到随着 SiO(2)模板初始比表面积的增加，锐钛矿相相对于金红石相的优先形成。将多孔 TiO(2) 微球用于气相中氮氧化物（NO(x)）的光催化降解。结果表明，与商业参考样品（Degussa 公司的 P25）相比，USP 制备的纳米结构 TiO(2) 样品具有显著更高的比表面积特异性活性。
