New technologies are needed for detection and identification of gaseous species in near-real time. Voltammetry, applied to cermet electrochemical cell microsensors, was shown in this study to be promising in its ability to discern and quantify gases. The miniature cermet cells were fabricated from ceramic, metallic, and metal oxide components, and reacted uniquely with gases and mixtures in the atmosphere. Neural net chemometrics algorithms were used to interpret the waveforms to extract information about the presence and concentration of constituent gases. Results to date have shown that these sensors can correctly identify more than thirty electroactive gases while showing a high tolerance for interferents. A single element sensor can determine gas concentrations from the part per million level to the percentage level while arrays provide even better detection and discrimination. This work focuses on four constituents of diesel exhaust: benzene, 1,3-butadiene, acrolein, and acetaldehyde. Voltammetric sensors demonstrated reproducible responses to four concentrations of each constituent spiked into diesel exhaust.
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