Photocatalytic TiO2 thin films by aerosol-deposition: From micron-sized particles to nano-grained thin film at room temperature

Abstract A nano-sized, TiO2 photocatalytic thin film with a dispersion of anatase crystallites was successfully fabricated from a micron-sized powder by aerosol deposition (AD) at room temperature (RT). Extremely rough, network-structured, photocatalytic thin films were obtained without any binder or heat treatment. The films were photocatalytically active under both ultraviolet (UV) and solar light as a result of their nano-sized, anatase grains and amorphous phase. Various photocatalytic evaluations confirmed the excellent photocatalytic performance of the AD TiO2 film in terms of organic degradation, pathogen disinfection, and hydrophilicity. This enhanced photocatalytic performance was attributed not only to the nano-crystalline anatase grains, but also to the exceptionally rough, network microstructure and nano-projections capable of supporting the enhanced loading of organic contaminants onto the film surface. Furthermore, because the nano-grained, AD TiO2 photocatalytic thin films were fabricated from low-cost, micron-sized powder with a deposition rate as high as 3 μm/min at RT, this process promises to be one of the most cost-effective methods for many practical photocatalyst applications.

[1]  F. Iskandar,et al.  Enhanced Photocatalytic Performance of Brookite TiO2 Macroporous Particles Prepared by Spray Drying with Colloidal Templating , 2007 .

[2]  K. Guan.  Relationship between photocatalytic activity, hydrophilicity and self-cleaning effect of TiO2/SiO2 films , 2005 .

[3]  N. Xu,et al.  Effects of Particle Size of TiO2 on Photocatalytic Degradation of Methylene Blue in Aqueous Suspensions , 1999 .

[4]  Ke‐long Huang,et al.  Investigation of photoelectrochemical oxidation of Fe2+ ions on porous nanocrystalline TiO2 electrodes using electrochemical quartz crystal microbalance , 2002 .

[5]  M. Stylidi.  Pathways of solar light-induced photocatalytic degradation of azo dyes in aqueous TiO2 suspensions , 2003 .

[6]  J. Ryu,et al.  Effects of Pb(Zn1∕3Nb2∕3)O3 addition and postannealing temperature on the electrical properties of Pb(ZrxTi1−x)O3 thick films prepared by aerosol deposition method , 2007 .

[7]  K. Hashimoto,et al.  Visible-light induced hydrophilicity on nitrogen-substituted titanium dioxide films. , 2003, Chemical communications.

[8]  R. Asahi,et al.  Visible-Light Photocatalysis in Nitrogen-Doped Titanium Oxides , 2001, Science.

[9]  Li Zhang,et al.  Application of nano TiO(2) towards polluted water treatment combined with electro-photochemical method. , 2003, Water research.

[10]  L. Miao,et al.  Microstructure and bactericidal ability of photocatalytic TiO2 thin films prepared by rf helicon magnetron sputtering , 2004 .

[11]  Pratim Biswas,et al.  Role of Synthesis Method and Particle Size of Nanostructured TiO2 on Its Photoactivity , 2002 .

[12]  T. Yoko,et al.  Photoelectrochemical and photocatalytic properties of multilayered TiO2 thin films with a spinodal phase separation structure prepared by a sol-gel process , 2005 .

[13]  Jun Akedo,et al.  Aerosol Deposition of Ceramic Thick Films at Room Temperature: Densification Mechanism of Ceramic Layers , 2006 .

[14]  Jong-Jin Choi,et al.  Oxidation Resistance Coating of LSM and LSCF on SOFC Metallic Interconnects by the Aerosol Deposition Process , 2007 .

[15]  P. Christensen,et al.  Photoelectrocatalysis by titanium dioxide for water treatment , 2006 .

[16]  R. Amal,et al.  Bactericidal effects of titanium dioxide-based photocatalysts , 2005 .

[17]  Woon-Ha Yoon,et al.  Fabrication and ferroelectric properties of highly dense lead-free piezoelectric (K0.5Na0.5)NbO3 thick films by aerosol deposition , 2007 .

[18]  J. Jokiniemi,et al.  Deposition of nanostructured titania films by particle-assisted MOCVD , 2005 .

[19]  R. Asahi,et al.  Band-Gap Narrowing of Titanium Dioxide by Nitrogen Doping , 2001 .

[20]  Dazhi Yang,et al.  Sol–gel deposited TiO2 film on NiTi surgical alloy for biocompatibility improvement , 2003 .

[21]  T. Yoko,et al.  Domain size change of spinodal phase separation structure in the sol-gel derived TiO2 thin film , 2006 .

[22]  L. Klimek,et al.  Plasma enhanced CVD deposition of titanium oxide for biomedical applications , 2005 .

[23]  C. Ni,et al.  Size dependency of nanocrystalline TiO2 on its optical property and photocatalytic reactivity exemplified by 2-chlorophenol , 2006 .

[24]  L. Ge,et al.  Fabrication, characterization and photocatalytic activities of TiO2 thin films from autoclaved-sol , 2007 .

[25]  J. S. Lees,et al.  A structural investigation of titanium dioxide photocatalysts , 1991 .

[26]  Dianzhong Wen,et al.  Antibacterial properties of Sb–TiO2 thin films by RF magnetron co-sputtering , 2007 .

[27]  B. Ohtani,et al.  Photocatalytic Activity of Amorphous−Anatase Mixture of Titanium(IV) Oxide Particles Suspended in Aqueous Solutions , 1997 .

[28]  Jong-Ha Choi,et al.  The effect of annealing on photocatalytic properties of nanostructured titanium dioxide thin films , 2007 .

[29]  R. Amal,et al.  Novel Photocatalyst: Titania-Coated Magnetite. Activity and Photodissolution , 2000 .

[30]  Jun Akedo,et al.  Microstructure and Electrical Properties of Lead Zirconate Titanate (Pb(Zr52/Ti48)O3) Thick Films Deposited by Aerosol Deposition Method , 1999 .