A facile one-step route to synthesize titania hollow microspheres with incontinuous multicavities

The titania hollow microspheres with incontinuous multicavities were successfully fabricated via an oil/water (O/W) emulsion process accompanied by sol–gel reaction in the presence of polyvinylpyrrolidone (PVP). In the one-step route, the addition of PVP to the tetrabutyl titanate (TBT) 1-octanol solution as the oil phase of the O/W emulsion clearly expands the size of the cavities inside the microspheres. The n-propanol and atoleine alters the polarity of the oil phase to affect the interior structure significantly. The Span 80 is used as a stabilizer to preserve spherical shape. A preliminary mechanism based on phase-separation for the structural evolution of titania hollow microspheres with multicavities is suggested. Zirconia and alumina hollow microspheres with incontinuous multicavities can also be prepared by this one-step route successfully.

Graphical abstractOne-step templateless method based on phase separation has been reported to fabricate hollow spheres with multicavities.Figure optionsDownload full-size imageDownload as PowerPoint slide