Freestanding doubly open-ended TiO2 nanotubes for efficient photocatalytic degradation of volatile organic compounds
By Weon, Seunghyun; Choi, Jongmin; Park, Taiho; Choi, Wonyong
Published in Applied Catalysis B: Environmental
2017
Abstract
Abstract We synthesized freestanding doubly open-ended TiO2 nanotubes (DNT) film and compared their photocatalytic activity and durability during the repeated degradation cycles of volatile organic compounds (VOCs) with those of TiO2 nanotubes (TNT) film. {DNT} exhibited higher activity and durability for the photocatalytic degradation of gaseous acetaldehyde and toluene than TNT. The doubly open-ended structure of {DNT} allows {O2} molecules to be easily supplied to the active sites, which increases not only the intrinsic photocatalytic activity but also the resistance to catalyst deactivation. The freestanding {DNT} film was additionally loaded with TiO2 nanoparticles (NP@DNT) in the inner wall to further increase the activity for {VOC} degradation. The photocatalytic activity of NP@DNT was higher than bare {DNT} and bare {TNT} by 1.3 and 1.8 times, respectively. Unlike the case of DNT, the TiO2 nanoparticles loaded {TNT} (NP@TNT) exhibited a lower activity than bare TNT, probably because the TiO2 nanoparticles blocked the {TNT} channels with hindering the mass transfer of {O2} and {VOC} molecules. {DNT} with doubly open-ended structure serves as a versatile platform of fabricating nanostructured photocatalysts with maintaining the open channel structure that facilitates the mass transfer of {O2} and {VOC} molecules.