Abstract
Through structure-monitoring of nanotube formation from a lamellar sodium titanate, the present work explicitly elucidated the structure of the titanate nanotubes obtained from hydrothermal treatment of TiO2 with NaOH. A new compound of an orthorhombic lepidocrocite-type sodium titanate was synthesized from calcination of a solid-state mixture of TiO2 anatase and Na2CO3 powders followed by hydrothermal treatment with NaOH. By treating with acid at 25°C for Na+ exchange with H3O+, the titanate compound exfoliated and then proceeded with sheet-scrolling to form nanotubes, which had a structure and morphology very close to those of the nanotubes derived from NaOH treatment on TiO 2. During the low-temperature acid treatment, the lepidocrocite-type titanate is transformed from the orthorhombic C-base-centered symmetry to the body-centered symmetry. This transformation, accompanied by a size-contraction of TiO6-octahedron units, was critical for the formation of nanotubes. The present work provides direct evidence, for the first time, that the widely reported TiO2-derived titanate nanotubes can be obtained at low temperatures by scrolling the sheets exfoliated from the orthorhombic lepidocrocite-type titanate.
Original language | English |
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Pages (from-to) | 3434-3438 |
Number of pages | 5 |
Journal | Langmuir |
Volume | 24 |
Issue number | 7 |
DOIs | |
Publication status | Published - 2008 Apr 1 |
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces
- Spectroscopy
- Electrochemistry