Spontaneous construction of photoactive hollow TiO2 microspheres and chains

Shengwei Liu, Jiaguo Yu*, Stephen Mann

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

68 Citations (Scopus)

Abstract

Discrete and chain-like aggregates of well-defined hollow TiO2 microspheres are reproducibly synthesized in high yield by a modified fluoride-mediated self-transformation strategy using urea as a base catalyst. The shell walls are composed of agglomerated polyhedral anatase nanocrystals, and exhibit hierarchical porosity. The addition of urea tunes the nucleation dynamics and surface states of the elementary TiO2 building blocks, which together promote the formation of metastable solid microparticles of uniform size that subsequently transform into morphologically invariant hollow microspheres and chain-like aggregates. The high surface area, bimodal mesoporosity of the shell walls, and increased band gap of the hollow TiO2 microspheres give rise to increases in photocatalytic activity when compared with anatase nanoparticles and aggregates prepared in the absence of urea.

Original languageEnglish
Article number325606
Number of pages7
JournalNanotechnology
Volume20
Issue number32
DOIs
Publication statusPublished - 12 Aug 2009

Keywords

  • INDUCED SELF-TRANSFORMATION
  • PHOTOCATALYTIC ACTIVITY
  • MESOPOROUS TITANIA
  • VISIBLE-LIGHT
  • SPHERES
  • MICROSTRUCTURES
  • WATER
  • NANOSPHERES
  • FABRICATION
  • CELLS

Cite this