title: On the photocatalytic properties of elongated TiO2 nanoparticles for phenol degradation and Cr(VI) reduction.
abstract: Elongated TiO(2) nanoparticles with high aspect ratio have specific advantages in separation processes. In this study, TiO(2) nanofiber was prepared via a hydrothermal reaction, and TiO(2) nanoparticles with varied structural properties were obtained using hydrothermal and calcination post-treatments. Photocatalytic phenol degradation and Cr(VI) reduction over these catalysts was investigated. Results showed that hydrothermally prepared TiO(2) nanofiber consisted of titanate with high aspect ratio. Calcining the as-prepared TiO(2) nanofiber at 400 and 600 degrees C led to the crystalline phase transformation from titanate to TiO(2)-B and to the presence of mixed crystalline phases composed of TiO(2)-B and anatase. In contrast, hydrothermal post-treatment results in the generation of pure anatase TiO(2) nanoparticles. For photocatalytic phenol degradation, calcining the as-prepared TiO(2) nanofiber resulted in an enhanced catalytic activity, whereas TiO(2) nanoparticles obtained by calcination post-treatment showed lower catalytic activities for photocatalytic Cr(VI) reduction compared to as-prepared TiO(2) nanofiber. TiO(2) nanofiber modified using the hydrothermal post-treatment, however, exhibited the highest catalytic activity among TiO(2) nanoparticles examined for both photocatalytic phenol degradation and Cr(VI) reduction. Furthermore, TiO(2) nanoparticles obtained by hydrothermal post-treatment showed the best sedimentation efficiency, highlighting its prominent potential as a readily separable and recoverable photocatalyst.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China.
authors.forename: Rongxin
authors.initials: R
authors.lastname: Mu
authors.forename: Zhaoyi
authors.initials: Z
authors.lastname: Xu
authors.forename: Liyuan
authors.initials: L
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Shao
authors.forename: Haiqing
authors.initials: H
authors.lastname: Wan
authors.forename: Shourong
authors.initials: S
authors.lastname: Zheng
mesh_terms: D002384:Catalysis; D002857:Chromium / Q000737:chemistry*; D003247:Conservation of Natural Resources; D003460:Crystallization; D004785:Environmental Pollutants / Q000737:chemistry*; D015386:Hazardous Substances; D006358:Hot Temperature; D057139:Nanofibers / Q000737:chemistry*; D010084:Oxidation-Reduction; D019800:Phenol / Q000737:chemistry*; D010782:Photolysis / Q000187:drug effects* / Q000528:radiation effects*; D014025:Titanium / Q000737:chemistry*
chemical_list: D004785:Environmental Pollutants; D015386:Hazardous Substances; D002857:Chromium; C009495:titanium dioxide; C074702:chromium hexavalent ion; D019800:Phenol; D014025:Titanium