In situ fabrication of TiO 2 nanotube arrays sensitized by Ag nanoparticles for enhanced photoelectrochemical performance

Photocatalytically Active TiO2/Ag2O Nanotube Arrays Interlaced with Silver Nanoparticles Obtained from the One-Step Anodic Oxidation of Ti–Ag Alloys

“…In the literature, the most often presented preparation routes of Ag-TiO 2 or Ag 2 O-TiO 2 photocatalysts have been electrochemical deposition, photodeposition, the precipitation method, the sputtering technique, , the chemical reduction method, − and γ-ray radiolysis. , Generally, Ag-TiO 2 or Ag 2 O-TiO 2 is prepared by a two-step synthesis process, which appears to be complicated and needed to accurately rationalize several parameters of preparation conditions. In contrast to the other methods, the electrochemical anodization approach provides a dense and well-defined layer, where NTs are perpendicularly aligned to the substrate surface.…”

Optimizing the photochemical conversion of UV–vis light of silver-nanoparticles decorated TiO2 nanotubes based photoanodes

“…The tendency that smaller Ag-NPs are more beneficial than larger ones in terms of photoconversion efficiency and/or photocatalytic degradation of pollutants has been confirmed by Liu et al [24], who controlled the size of the NPs through the electrodeposition time of the Ag-NPs onto the TiO 2 -NTs. They found that Ag-NPs with ∼13 nm diameter (obtained after 90 s of electrodeposition) leads to a remarkable degradation of methyl orange after 150 min under visible radiation, as a consequence of the Ag-NPs plasmonic resonance that enhances the absorption of the Ag-NPs/TiO 2 -NTs hybrid structures in the visible range [25]. While the full understanding of the origin of the beneficial effects of adding Ag-NPs to TiO 2 -NTs is still to come, some authors attributed the Ag-NPs enhanced absorption to the formation of Schottky heterojunctions at the interface of Ag-NPs and TiO 2 -NTs' surface, which practically translated into a sizeable increase of the generated photocurrent under visible light (for λ>400 nm) [25].…”

“…They found that Ag-NPs with ∼13 nm diameter (obtained after 90 s of electrodeposition) leads to a remarkable degradation of methyl orange after 150 min under visible radiation, as a consequence of the Ag-NPs plasmonic resonance that enhances the absorption of the Ag-NPs/TiO 2 -NTs hybrid structures in the visible range [25]. While the full understanding of the origin of the beneficial effects of adding Ag-NPs to TiO 2 -NTs is still to come, some authors attributed the Ag-NPs enhanced absorption to the formation of Schottky heterojunctions at the interface of Ag-NPs and TiO 2 -NTs' surface, which practically translated into a sizeable increase of the generated photocurrent under visible light (for λ>400 nm) [25]. On the other hand, the presence of Ag-NPs at the surface of TiO 2 -NTs has been associated with the extension of the lifetime of the photogenerated charges, as a consequence of the trapping in the Ag-NPs of the electrons photogenerated in the conduction band of TiO 2 [26][27][28].…”