Synthesis and characterization of N-modified titania nanotubes for photocatalytic applications

Abstract

The modification of titanate nanotubes (TiNT) with nitrogen (NTiNT) was accomplished through impregnation method. TiNT were synthesized via hydrothermal treatment of titania powders in NaOH solution at 130 °C for 48 h. The obtained samples were characterized by UV-Vis absorption spectroscopy, Brunauer-Emmett-Teller (BET) surface area, XRD, TEM, XPS, and TG analysis. Structure, morphology, composition, and visible light absorption property of nitrogen-modified TiO2 nanotubes are found to depend on the nitrogen content and not on the calcination temperature for the range used in this work. The photocatalytic activity of these nanotubes was investigated for the degradation of methylethylketone (MEK) and hydrogen sulfide (H2S) under ultraviolet and solar light radiation. MEK is very resistant to photocatalytic degradation with the prepared materials;, however, the results show that modification of the TiNT with nitrogen in a proportion of 1 to 1 (TiNT to urea weight ratio) and calcination at 400 °C lead to materials with high photocatalytic activity under ultraviolet radiation and moderate photocatalytic activity under solar radiation for degradation of H2S.

Enhanced photocatalytic activity of Se-doped TiO2 under visible light irradiation

“…Many efforts have been devoted to overcome the shortcomings and enhance the photocatalytic properties of TiO 2 , especially in the visible light range. For example, ion doping 3 – 7 , anatase-rutile phase coexisting 8 , or p-n heterojunction formation 9 , were explored. Among them, ion doping was an efficient approach 10 .…”

Disparate roles of doped metal ions in promoting surface oxidation of TiO 2 photocatalysis

“…Three main strategies have been adopted to strengthen surface-charge separation or broadening the photoabsorption, including metal or non-metal (ion) doping [13][14][15][16][17], anatase-rutile [18] or p-n [19] heterojunction formation and compounding with charge transfer materials [20][21][22]. Among these attempts, metal ion doping has proven to be a simple and valid way to promote photonic efficiency due to the efficient charge transfer from the doped metal ions to Ti 4 + ions [23,24].…”