Title :
Comparative study of the gasochromic performance of Pd/WO3 and Pt/WO3 nanotextured thin films for low concentration hydrogen sensing
Author :
Yaacob, M.H. ; Breedon, M. ; Kalantar-zadeh, K. ; Wlodarski, W. ; Li, Y.
Author_Institution :
Sch. of Electr. & Comput. Eng., RMIT Univ., Melbourne, VIC, Australia
Abstract :
The gasochromic performance of WO3 nanotextured thin films coated with catalytic Pd or Pt layers were investigated for low concentration H2 sensing. The 25¿ thick catalytic metals were deposited onto 200nm thick sputtered WO3 films. It was found that the Pd/WO3 thin films show superior gasochromic response when compared with Pt/WO3 thin films. Integrating the absorbance change over a range of visible wavelengths (500-800nm), has enabled very low concentrations of H2 (0.06%) to be easily sensed in real time for both Pd/WO3 and Pt/WO3 thin films. Pd/WO3 T90% response towards 0.06% H2 in a balance of synthetic air was 30 seconds at 100°C. Similarly, higher H2 concentrations of 1% can be accurately sensed in as little as 20 seconds.
Keywords :
air; catalysis; gas sensors; hydrogen; metal-insulator boundaries; metallic thin films; nanosensors; nanostructured materials; platinum; thin film sensors; tungsten compounds; H2; Pd-WO3; Pt-WO3; absorbance; catalytic layers; gasochromic performance; low concentration hydrogen sensing; nanotextured thin films; size 200 nm; size 25 A; synthetic air; temperature 100 degC; time 20 s; time 30 s; wavelength 500 nm to 800 nm; Coatings; Control systems; Hydrogen; Optical devices; Optical films; Optical sensors; Scanning electron microscopy; Sputtering; Transistors; Tungsten;
Conference_Titel :
Sensors, 2009 IEEE
Conference_Location :
Christchurch
Print_ISBN :
978-1-4244-4548-6
Electronic_ISBN :
1930-0395
DOI :
10.1109/ICSENS.2009.5398154
