Abstract
TiO2nanotube arrays sensitized with ZnFe2O4nano-crystals were successfully fabricated by a two-step process of anodization and a vacuum-assistant impregnation method followed by annealing. The sample was studied by an environmental scanning electron microscope, a transmission electron microscope, energy-dispersive X-ray analysis, and X-ray diffraction to characterize its morphology and chemical composition. Ultraviolet-visible (UV-vis) absorption spectra and a photoelectrochemical measurement approved that the ZnFe2O4sensitization enhanced the probability of photoinduced charge separation and extended the range of the photoresponse of TiO2nanotube arrays from the UV to visible region. In addition, the behaviors of photoinduced charge transfer in a TiO2nanotube array electrode before and after sensitization by ZnFe2O4nanocrystals were comparatively studied. The photoluminescence of the TiO2nanotube array electrode became suppressed, and the surface photovoltage responses on the spectrum were significantly enhanced after the introduction of ZnFe2O4nanocrystals. The transfer dynamics of the photoinduced charges were observed directly by a transient photovoltage measurement, which revealed a fast charge separation at the interface between ZnFe2O4nanocrystals and TiO2nanotubes upon light excitation.
Original language | English |
---|---|
Pages (from-to) | 3113-3120 |
Number of pages | 8 |
Journal | Langmuir |
Volume | 27 |
Issue number | 6 |
DOIs | |
Publication status | Published - 15 Mar 2011 |
Externally published | Yes |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Surfaces and Interfaces
- Spectroscopy
- Electrochemistry