Development of room temperature vapor sensor system based on tungsten organometallic-PANi thin film

The aim of this research is to develop vapor sensor system which works at room temperature. The development of system was used to test vapor sensing properties of tungsten organometallic-PANi thin film towards isopropanol and ethanol vapors. Tungsten organometallic solution was prepared by sol gel method. Commercial PANi powder were directly added into tungsten organometallic solution to form composite solution. Five layers of the solution were deposited onto SiO₂ coated silicon substrate using spin coating technique for fabrications of vapor sensing device. The vapor sensing test revealed that the composite film was responsive towards isopropanol and ethanol vapors with sensitivity of 5.58% and 4.76% each. The reversibility of sensor towards isopropanol vapor is 1.37 and towards ethanol vapor is 1.16. Meanwhile the response time for the sensor towards isopropanol vapor is 81 s and towards ethanol vapor is 108 s. The recovery time towards both vapors are same i.e. 189 s.