Distinction between alcohols and hydrocarbons with a semiconductor gas sensor depending on the range and frequency of a cyclic temperature

Abstract

The dynamic nonlinear response of a semiconductor gas sensor was investigated to enhance the selectivity of the sensor response toward sample gases. A cyclic temperature composed of a fundamental harmonic was applied to a SnO₂ semiconductor gas sensor and the resulting conductance of the sensor was evaluated by fast Fourier transformation (FFT). The dynamic nonlinear responses to samples (hydrocarbons and alcohols) were further characterized depending on the range and frequency of the cyclic temperature. These characteristic sensor responses were considered theoretically based on a reaction–diffusion model for the semiconductor surface.