混晶海胆状TiO2空心球多级结构的制备及其对亚甲基蓝的光催化降解

Preparation and Photocatalytic Degradation of Methylene Blue of Hierarchical Mixed-Phase Urchin-like TiO2 Hollow Spheres

用简单的无模板水热法可控合成了金红石相锥刺和锐钛矿相空心球的海胆状TiO2多级结构。研究了制备介质pH值和反应时间对形貌的影响。空心球上锥刺的密度可以通过改变反应条件加以调控。对海胆状TiO2多级结构可能的形成机理进行了研究。将不同锥刺密度的TiO2空心球应用于亚甲基蓝降解的光催化研究,结果表明低锥刺密度的TiO2空心球的光催化效果优于P25-TiO2,更优于锥刺多和无锥刺的光滑TiO2空心球。

Hierarchical urchin-like TiO2 hollow spheres comprising rutile phase of thorn and anatase phase of hollow shell was synthesized via a simple H2O2 assisted hydrothermal method.The effects of the pH value of preparation medium and the hydrothermal treatment time on the resulting TiO2 morphology and structure were systematically investigated.The density of the thorns on the surface of hollow spheres can be effectively modified by tuning the pH value of preparation medium.A possible growth mechanism of the hierarchical structure was proposed.Photocatalytic degradation of methylene blue over the obtained TiO2 hollow spheres with different density of rutile thorn was explored.It was revealed that the TiO2 hollow spheres with less thorns outperformed the well-known photocatalyst P25-TiO2,and were much better than the TiO2 hollow spheres with more thorns and the smooth TiO2 hollow spheres.