Co3O4-based isobutane sensor operating at low temperatures

Co3O4 ceramic was utilized to fabricate a low temperature-operating butane gas sensor because the oxide strongly catalyzes the oxidation reaction of m ethane that is chemically the most stable hydrocarbon. The CO3O4 sensor has shown high sensitivity to isobutane even at 250 degreesC. However, the sen sor was very unstable on consecutive measurements. It might be due to the p resence of oxides in several valence states. As a stabilizer. 10-50 wt.% Ni O powders were added to the Co3O4 ceramic because NiO is only oxide form in NiO system. The CO3O4-NiO sensor exhibits excellent repeatability on conse cutive measurements as well as long-term stability. (C) 2001 Elsevier Scien ce B.V. All rights reserved.