Application of V2O5/WO3/TiO2 for Resistive-Type SO2 Sensors

A study on the application of V2O5/WO3/TiO2 (VWT) as the sensitive material for resistive-type SO2 sensor was conducted, based on the fact that VWT is a well-known catalyst material for good selective catalytic nitrogen oxide reduction with a proven excellent durability in exhaust gases. The sensors fabricated in this study are planar ones with interdigitated electrodes of Au or Pt. The vanadium content of the utilized VWT is 1.5 or 3.0 wt%. The resistance of VWT decreases with an increasing SO2 concentration in the range from 20 ppm to 5,000 ppm. The best sensor response to SO2 occurs at 400 °C using Au electrodes. The sensor response value is independent on the amount of added vanadium but dependent on the electrode materials at 400 °C. These results are discussed and a sensing mechanism is discussed.

[1]  Pullur Anil Kumar,et al.  SO 2 resistant antimony promoted V 2O 5/TiO 2 catalyst for NH 3-SCR of NO x at low temperatures , 2008 .

[2]  Harvey G. Stenger,et al.  Oxidation of sulfur dioxide to sulfur trioxide over supported vanadia catalysts , 1998 .

[3]  Jan Erik Johnsson,et al.  Deactivation of V2O5-WO3-TiO2 SCR catalyst at a biomass-fired combined heat and power plant , 2005 .

[4]  Pullur Anil Kumar,et al.  SO2 resistant antimony promoted V2O5/TiO2 catalyst for NH3-SCR of NOx at low temperatures , 2008 .

[5]  Karl Schermanz,et al.  High-temperature stability of V2O5/TiO2-WO3-SiO2 SCR catalysts modified with rare-earths , 2006 .

[6]  Guido Busca,et al.  Chemical and mechanistic aspects of the selective catalytic reduction of NOx by ammonia over oxide catalysts: A review , 1998 .

[7]  John F. Vetelino,et al.  A semiconducting metal oxide sensor array for the detection of NOx and NH3 , 2001 .

[8]  Ming-Yen Wey,et al.  Effects of particulates, heavy metals and acid gas on the removals of NO and PAHs by V2O5-WO3 catalysts in waste incineration system. , 2009, Journal of hazardous materials.

[9]  S. Bhoga,et al.  Electrochemical solid state gas sensors: An overview , 2007 .

[10]  Pio Forzatti,et al.  Catalytic properties in deNOx and SO2–SO3 reactions , 2000 .

[11]  R. G. Egdell,et al.  Application of V-doped TiO2 as a sensor for detection of SO2 , 2001 .

[12]  Jeong Hoi Goo,et al.  Effects of NO2 and SO2 on selective catalytic reduction of nitrogen oxides by ammonia. , 2007, Chemosphere.

[13]  Ralf Moos,et al.  Zeolite cover layer for selectivity enhancement of p-type semiconducting hydrocarbon sensors , 2008 .

[14]  Ralf Moos,et al.  Vanadia doped tungsten–titania SCR catalysts as functional materials for exhaust gas sensor applications , 2011 .

[15]  Motonobu Kobayashi,et al.  V2O5-WO3/TiO2-SiO2-SO42− catalysts: Influence of active components and supports on activities in the selective catalytic reduction of NO by NH3 and in the oxidation of SO2 , 2006 .

[16]  R. Kassing,et al.  Selectivity enhancement of a WO3/TiO2 gas sensor by the use of a four-point electrode structure , 2003 .

[17]  Toshiyuki Naito,et al.  Mercury Oxidation over the V2O5(WO3)/TiO2 Commercial SCR Catalyst , 2008 .

[18]  Philippe Knauth,et al.  Solute segregation, electrical properties and defect thermodynamics of nanocrystalline TiO2 and CeO2 , 2000 .

[19]  C. A. Powell,et al.  Materials challenges in advanced coal conversion technologies , 2008 .

[20]  Biao Wang,et al.  Solid-state potentiometric SO2 sensor combining NASICON with V2O5-doped TiO2 electrode , 2008 .

[21]  Maximilian Fleischer,et al.  Selective Mixed Potential Ammonia Exhaust Gas Sensor , 2009 .

[22]  Maximilian Fleischer,et al.  Investigation of the electrode effects in mixed potential type ammonia exhaust gas sensors , 2011 .

[23]  Ralf Moos,et al.  Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment , 2010, Sensors.

[24]  Pio Forzatti,et al.  Present status and perspectives in de-NOx SCR catalysis , 2001 .

[25]  Jorge R. Frade,et al.  Detection mechanism of TiO2-based ceramic H2 sensors , 1999 .