Efficient silver modification of TiO2 nanotubes with enhanced photocatalytic activity

In this paper, Ag(CH3NH2)(2)(+), Ag(NH3)(2)(+) and Ag+ with different radii have been used as silver sources to find out the distribution of Ag ions on the H-TNT surface, which is critical to the final performance. The influence of this distribution on visible photocatalytic activity is further studied. The results indicate that, when Ag+ used as silver source with low concentration, these small sized silver ions mainly distribute on interlayer spacing of H-TNT. After heat-treatment and photo-reduction, the generated silver nanoparticles uniformly embed in the anatase TiO2 nanotube walls, and bring large interfacial area between Ag particles and TiO(2 )nanotubes. The separation effect of photogenerated electron-hole pair in TiO2 is enhanced by Ag particles, and achieves the best at 0.15 g/L, much higher than P25, TiO2/0, Ag-N@TiO(2 )and Ag-C-N@TiO2 . This paper provides new ideas for the modification of TiO2 nanotubes. (C) 2018 Published by Elsevier Masson SAS.