Gas sensing properties of tungsten organometallic-PANi thin film at room temperature

Tungsten organometallic sol and tungsten-organometallic-PANi sol were deposited onto silicon substrates by a sol-gel spin coating technique. XRD characterization showed that the WO₃ monoclinic crystal structure was formed after WO₃ powder was annealed at 400 °C for 2 hours. Microstructural studies by SEM indicate that addition of commercial polyaniline (PANI) powder into tungsten organometallic sol caused the film to be flat and smooth. Tungsten organometallic sensor was responsive towards isopropanol vapor but the response decrease with time. Reuse of this sensor for the next detection showed that the sensor was not responsive to ethanol vapor. The addition of PANi into tungsten organometallic sol improved the sensing properties of the sensor. Tungsten organometallic-PANi sensor exhibited good reversibility, reusability and was responsive towards isopropanol and ethanol vapors.