Abstract
A xylene sensor using a double-layered metal-oxide thin film and Ni-catalyst deposited on a porous alumina is presented. The sensing film has a double-layered structure; the first layer is Fe2O3+TiO2 (5mol%)+MgO (4mol%), and the second layer is WO3+TiO2 (10mol%). The thicknesses of the first and second layers are 200nm and 70nm, respectively. Both response and stability are improved by adopting a double-layered structure. The Ni-deposited porous alumina is placed over the sensing film. The pores in the porous alumina are cylindrical. The inner diameter and the height of the pores are about 200nm and 60μm, respectively. Xylene gas goes through the Ni-deposited pores in the porous alumina to reach the sensing film. The catalytic action of the deposited Ni enhances the chemical activity of xylene gas and the amount of its absorption on the sensing film. Thus the sensor is highly sensitive to xylene gas. The sensor is capable of detecting xylene at a concentration as low as 0.07ppm. Moreover, the selectivity to xylene gas is satisfactory. The response and recovery times are approximately 20s and 300s, respectively, at an operating temperature of 340°C. All films and Ni are deposited by rf sputtering while the porous alumina is formed by anodic oxidation of aluminum.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
