Oxygen sensors thin films

A thin film dissolved oxygen sensor was fabricated by entrapping erythrosin B in a sol-gel matrix95. The silica sol-gel doped with the dye was deposited onto the cleaned glass slides by the spin-coating method. The sensor was linear in the most useful range of dissolved oxygen concentrations, up to 9.1 mg l 1 concentration obtained in air saturated water at 20 °C. 

McDonagh C., Bowe P., Mongey K., MacCraith B., Characterisation of porosity and sensor response times of sol-gel-derived thin films for oxygen sensor applications, J. Non-Cryst. Solids 2002 306 138-148. 

Izu, N. Murayama, N. Shin, W. Matsubara, I. Kanzaki, S. 2004. Resistive oxygen sensors using cerium oxide thin films prepared by metal organic chemical vapor deposition and sputtering. Jpn. J. Appl. Phys. 43 6920-6924. 

Beie, H. J. Gnorich, A. 1991. Oxygen gas sensors based on Ce02 thick and thin films. Sens. Actuators B 4 393-399. 

In the above-described set-up (Fig. 8.16), the physical absorption of oxygen in water was used to measure the gas to liquid mass transfer. Thin-film fluorescence quenching-based sensors were installed to determine the oxygen concentration at the inlet and exit of the reactor. From the measured oxygen concentrations, the mass transfer coefficient was calculated based on the reactor-based liquid velocity ... 

WO3 thin films activated by An layers have been used [625]. This type of material possesses excellent sensitivity towards NO and NO2 gases. An exhaust gas NOj sensor that uses a platinum-gold alloy electrode to selectively remove oxygen but not NO was also reported [626]. 

Saji, K., Kondo, H., Takahashi, H.. Futata, H.. Angata, K. and Suzuki. T. (1993) Development of a thin-film oxygen sensor for combustion control of gas appliances. Sens. Actuators B, 14 (1-3), 695-6. 

It is also essential to know the cross-sensitivity of the zirconia single-crystal sensors to other gases. Sensors with porous Pt electrodes are known to be sensitive to gases such as CO at low temperatures [41], and in fact, this cross-sensitivity has been proposed as a principle for carbon monoxide sensors at low temperatures by some researchers [42, 43]. This effect is attributed to the ability of CO to compete successfully with oxygen for adsorption sites on Pt at temperatures from 500°C to 650°C. It was observed that the zirconia single-crystal sensor with thin-film Pt-Zr02-Y2O3 electrodes is less sensitive to CO than similar polycrystalhne sensors with porous Pt electrodes, but small em/errors still occur at 300-360°C. 

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