摘要
We report the photo-electro-chemical properties of Carbon Quantum Dots(CQD) functionalised TiO_2 nanotube arrays(TNA). The TNA formed by electrochemical anodization of a Ti foil offer highly aligned,vertically oriented nanostructures suitable for photo-catalytic application. These nanostructures are functionalised with CQDs synthesized by the electrochemical etching of graphite and the resultant samples are characterized by high resolution transmission electron microscopy,photo-current and photon-charge conversion efficiency measurements,Mott-Schottky and impedance spectroscopy. The results indicate that the nanotubes with larger diameter can support a higher density of CQDs and hence shows better values for photo-current and light conversion efficiency. Furthermore,these samples offer a lower charge transfer resistance across the semiconductorelectrolyte interface. The CQD functionalised TiO_2 nanotubesarrays with suitable diameter can therefore be used for efficient hydrogen generation by water splitting under the illumination of solar radiation.
We report the photo-electro-chemical properties of Carbon Quantum Dots(CQD) functionalised TiO_2 nanotube arrays(TNA). The TNA formed by electrochemical anodization of a Ti foil offer highly aligned,vertically oriented nanostructures suitable for photo-catalytic application. These nanostructures are functionalised with CQDs synthesized by the electrochemical etching of graphite and the resultant samples are characterized by high resolution transmission electron microscopy,photo-current and photon-charge conversion efficiency measurements,Mott-Schottky and impedance spectroscopy. The results indicate that the nanotubes with larger diameter can support a higher density of CQDs and hence shows better values for photo-current and light conversion efficiency. Furthermore,these samples offer a lower charge transfer resistance across the semiconductorelectrolyte interface. The CQD functionalised TiO_2 nanotubesarrays with suitable diameter can therefore be used for efficient hydrogen generation by water splitting under the illumination of solar radiation.
引文
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