Photoinduced desorption in ferrocene-ethanol vapor system using polychromatic light source: dependence on light intensity

The photoeffects at 290 K on a ferrocene sample adsorbed with ethanol vapor in a sandwich-type of cell configuration have been studied with various intensities of light from a mercury lamp by monitoring electrical current. Decrease in the measured current under light exposure has been observed at each light intensity. Termination of the light exposure resulted in an enhancement in current value. The analysis of the rates of the photoinduced changes in current under illumination at various intensities indicated the photoinduced desorption of ethanol vapor from the ferrocene surface at each intensity of light used. Similar analysis of the rates of the change of current after the termination of light exposure indicated the possibility of re-adsorption of vapor by the sample. A mathematical analysis of the dependence of photoinduced current on the light intensities has been attempted. Similar studies have been extended for some ferrocene derivatives. The possibility of application of such photoinduced desorption in ethanol vapor sensors has been discussed.