无模板法可控合成多层次结构二氧化钛微球

以1,4-二氧六环为溶剂,采用溶剂热法成功实现无模板法可控合成二氧化钛多层次结构微球。通过系统改变反应体系中浓盐酸与四异丙醇钛(TTIP)相对物质的量比能够有效调控二氧化钛形貌。当浓盐酸与TTIP物质的量比控制在0(或0.7或0.9)、1.8、3.6与5.7时,所得产物分别为纳米颗粒构建二氧化钛微球、纳米棒修饰二氧化钛微球、纳米棒花菜结构以及纳米棒海胆结构。在成功进行形貌调控的基础上,进一步探讨了二氧化钛多种结构的形成机理,并对其光催化产氢性能进行了表征。研究发现,在这4种结构中,纳米棒修饰二氧化钛微球具有最佳的光催化性能,这可能是由于同时存在金红石和锐钛矿两种晶型而形成异质结结构所导致。

Template-free Synthesis of Hierarchical Titania Microspheres with Controlled Morphology Evolution

Template-free synthesis of hierarchical TiO₂ microspheres with controlled morphology evolution was achieved by simply varying the molar ratio of HCl/TTIP under solvothermal reaction in 1,4-dioxane. By syste-matically controlling the HCl/TTIP molar ratio from 0 (or 0.7,0.9) to 1.8,3.6 and 5.7, nanoparticulate microspheres, microspheres decorated with nanorods, nanorod cauliflowers, and nanorod sea urchin structures were synthesized respectively. The mechanism for the morphology evolution was discussed. The photocatalytic performance of the TiO₂ microspheres with different morphologies for water splitting was investigated.It was found that the microspheres decorated with nanorods exhibited the best performance due to the coexistence of anatase and rutile phases.