Enhanced toluene sensing characteristics of TiO2-doped flowerlike ZnO nanostructures

Abstract The large-scale flowerlike ZnO nanostructures, consisting of many aggregative nanorods with the diameter of about 60 nm, were prepared by a simple and facile hydrothermal route. The toluene sensing properties of the pure ZnO and TiO 2 -doped ZnO nanostructures were tested at different operating temperatures from 160 to 390 °C and toluene concentrations ranging from 1 to 3000 ppm. The results indicate that the response of the ZnO nanostructures towards toluene was enhanced significantly by TiO 2 doping, which was deposited onto the ZnO products by evaporation. It is found that the TiO 2 -doped ZnO sensor exhibits remarkably enhanced response of 17.1 at the optimal operating temperature of 290 °C to 100 ppm toluene, which has been improved up from 7.4 at 390 °C from pure ZnO nanostructures.

[1]  Qing Peng,et al.  High ethanol sensitive SnO2 microspheres , 2006 .

[2]  Zhong Lin Wang,et al.  Large-Scale Hexagonal-Patterned Growth of Aligned ZnO Nanorods for Nano-optoelectronics and Nanosensor Arrays. , 2004, Nano letters.

[3]  D. C. Reynolds,et al.  Optically pumped ultraviolet lasing from ZnO , 1996 .

[4]  Ning Wang,et al.  Synthesis and characterization of waxberry-like microstructures ZnO for biosensors , 2008 .

[5]  J. Morante,et al.  Micromachined twin gas sensor for CO and O2 quantification based on catalytically modified nano-SnO2 , 2006 .

[6]  R. Bos,et al.  Alcohol and sulphate intermediates in the metabolism of toluene and xylenes to mercapturic acids , 1981, Journal of applied toxicology : JAT.

[7]  Nicolae Barsan,et al.  Direct formation of highly porous gas-sensing films by in situ thermophoretic deposition of flame-made Pt/SnO2 nanoparticles , 2006 .

[8]  Partha Mitra,et al.  Chemically deposited zinc oxide thin film gas sensor , 1999 .

[9]  Taihong Wang,et al.  Rapid and ultrahigh ethanol sensing based on Au-coated ZnO nanorods , 2008, Nanotechnology.

[10]  S. Shishiyanu,et al.  Sensing characteristics of tin-doped ZnO thin films as NO2 gas sensor , 2005 .

[11]  Jin-seong Park,et al.  ZnO sol–gel derived porous film for CO gas sensing , 2003 .

[12]  Kengo Shimanoe,et al.  Sensing properties of Au-loaded SnO2–Co3O4 composites to CO and H2 , 2005 .

[13]  Antonello Cutolo,et al.  Alcohol detection using carbon nanotubes acoustic and optical sensors , 2004 .

[14]  Sol–gel TiO2 and W/TiO2 nanostructured thin films for control of drunken driving , 2002 .

[15]  R. N. Karekar,et al.  Formulation and characterization of ZnO:Sb thick-film gas sensors , 1998 .

[16]  Hao Gong,et al.  Nano-crystalline Cu-doped ZnO thin film gas sensor for CO , 2006 .

[17]  P. Moseley.  New trends and future prospects of thick- and thin-film gas sensors , 1991 .

[18]  Fabio Quaranta,et al.  Oxygen gas-sensing characteristics for ZnO(Li) sputtered thin films , 1992 .

[19]  Yiying Wu,et al.  Room-Temperature Ultraviolet Nanowire Nanolasers , 2001, Science.

[20]  Chandrakant D. Lokhande,et al.  Enhanced response of porous ZnO nanobeads towards LPG: Effect of Pd sensitization , 2007 .

[21]  Chandrakant D. Lokhande,et al.  LPG sensing properties of ZnO films prepared by spray pyrolysis method : Effect of molarity of precursor solution , 2007 .

[22]  Masanobu Matsuguchi,et al.  Chemically modified copolymer coatings for mass-sensitive toluene vapor sensors , 2008 .

[23]  Khalil Arshak,et al.  Development of a novel gas sensor based on oxide thick films , 2005 .

[24]  Single step deposition of different morphology ZnO gas sensing films , 2007 .

[25]  Min-Hsiung Hon,et al.  The effects of thickness and operation temperature on ZnO:Al thin film CO gas sensor , 2002 .

[26]  Tongtong Wang,et al.  Contact-controlled sensing properties of flowerlike ZnO nanostructures , 2005 .

[27]  Hongjie Dai,et al.  Functionalized Carbon Nanotubes for Molecular Hydrogen Sensors , 2001 .

[28]  Zhong Lin Wang,et al.  Mesoporous polyhedral cages and shells formed by textured self-assembly of ZnO nanocrystals. , 2003, Journal of the American Chemical Society.

[29]  H. S. Maiti,et al.  A wet-chemical process to form palladium oxide sensitiser layer on thin film zinc oxide based LPG sensor , 2004 .