Increasing the sensitivity and selectivity of Metal Oxide gas sensors by controlling the sensitive layer polarization

Abstract

The effects of bias current on sensitivity and selectivity of resistive Metal-Oxide (MOX) sensors toward gases have been investigated. While the working temperature is kept constant, it has been found that tuning the polarization of the MOX thin film induces changes on its sensitivity toward gases. Besides, the behavior of sensitivity versus bias current depends on the nature of the gas and of the thin sensing film, meaning it is possible to enhance the selectivity by adjusting the polarization of different sensitive layers. This underutilized parameter provides a new way of improving easily gas sensors sensitivity and above all selectivity. It would then be interesting to polarize individually each sensor of a multi-sensor device in order to optimize the whole system performances, which may represent a breakthrough in the development of smart E-Nose. I.

Review: Influences of Semiconductor Metal Oxide Properties on Gas Sensing Characteristics

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Nonlinear behaviour of self-excited microcantilevers in viscous fluids

“…The second term is proportional to the velocity of the beam and accounts for the viscous drag force exerted by the fluid on the moving cantilever. These two components can therefore be described as an added mass, m A , and an added damping coefficient, c A [34,35]:…”

“…The parameter δ (ω) = 2η ρω is the thickness of the layer of fluid that surrounds the beam, which depends on the fluid viscosity, η, the fluid density, ρ, and on the angular frequency of oscillation, ω. L and W represent the length and width of the cantilever, respectively [35].…”

Precise Detection and Quantitative Prediction of Blood Glucose Level With an Electronic Nose System

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