Preparation and structure dependence of H2 sensing properties of palladium-coated tungsten oxide films》.pdfVIP

Sensors and Actuators B 177 (2013) 1062–1070 Contents lists available at SciVerse ScienceDirect Sensors and Actuators B: Chemical j o u rn a l h o me p a g e : w w w. elsev /locate/snb Preparation and structure dependence of H2 sensing properties of palladium-coated tungsten oxide films Meng Zhao a,b , Jianxing Huang a , Chung-Wo Ong a,∗ a Department of Applied Physics and Materials Research Center, The Hong Kong Polytechnic University, Hong Kong, PR China b Department of Electronic Science and Technology, Changzhou University, Changzhou, 213614, PR China a r t i c l e i n f o a b s t r a c t Article history: This study aims at revealing and explaining the influences of preparation condition on the structure and Received 12 September 2012 subsequent hydrogen (H2 ) sensing properties of palladium-(Pd-) coated tungsten oxide (WO3 ) films. The Received in revised form material structure was specified by grain size; porosity, surface roughness and thickness of the WO3 26 November 2012 layer; and thicknesses of the Pd coating. The structural parameters are found to be tailorable in broad Accepted 4 December 2012 Available online 12 December 2012 ranges by applying supersonic cluster beam deposition or magnetron sputtering technique operating at various substrate temperatures (50–550 ◦ C) and 20% Ar-80% O2 pressures (3–60 mTorr). The H2 sensing response of the sensors, and their response time (trespond ) for