NO₂-selective electrochemical sensors for Diesel exhausts

Jean-Paul Viricelle (1, 2, 3) , Philippe Vernoux (4) , Jing Gao (1, 2, 3) , Ivan Romanytsia (1, 2, 3) , Philippe Breuil (1, 2, 3) , Christophe Pijolat (1, 2, 3)

1 PRESSIC-ENSMSE - Procédés et REactivité des Systèmes Solide-gaz, Instrumentation et Capteurs
2 LGF-ENSMSE - Laboratoire Georges Friedel
3 SPIN-ENSMSE - Centre Sciences des Processus Industriels et Naturels
4 IRCELYON - Institut de recherches sur la catalyse et l'environnement de Lyon

Electrochemical NOx sensors based on yttria-stabilized zirconia (YSZ) are commercialized to detect overall NOx concentrations in Diesel exhausts without distinction between NO and NO₂. To overcome this inconvenient, a high-sensitive sensor based on selective electrochemical reduction of NO₂ is proposed. An electrochemical cell consisting of three metallic electrodes on solid-state electrolyte (YSZ) operating under electric polarization between a gold working electrode and a platinum counter electrode allows selective NO₂ detection at 400-550°C with high sensitivity, and without any significant interferences to other gases like hydrocarbons, carbon monoxide and also ammonia and nitrogen monoxide. A mechanism based on cathodic overpotential is proposed.

Mots clés: mixed potential; YSZ; exhaust; NOx sensor; polarization; overpotential

Domaines: Génie des procédés

Jean-Paul Viricelle, Philippe Vernoux, Jing Gao, Ivan Romanytsia, Philippe Breuil, et al.. NO₂-selective electrochemical sensors for Diesel exhausts. EUROSENSORS 2016, Hungarian Academy of Sciences; Akadémiai Kiadó / AKCongress, Sep 2016, Budapest, Hungary. pp.7 à 10, ⟨10.1016/j.proeng.2016.11.112⟩. ⟨hal-01379516⟩