Noboru Yamazoe

Hydrogen Peroxide Sensor Based On Carbon Electrode Loaded With Perovskite-type Oxide

Electromotive force (EMF) of the carbon electrode leaded with L,ao6Ca0.4Ni0.7Fe0.303 was found to vary logarithmically with the H202 concentration between 1 0-5 and 10-3M. The 90% response time was ca. 5 min at 25°C. The electrode loaded with large surface am perovskite-type oxide gave high activity to the electrochemical oxidation of H202, a limiting current was observed at the potential range between +0.6 and +1.0 V (vs. SCE). The sensing current of the carbon electrode loaded with hO&a().4Mn03 was found to be approximately proportional to H202 concentration up to 0.5 mM. The response time was as short as ca. 60 s at 25°C.

チタン酸塩を用いた半導体センサの高温における NOx 検知特性

A series of metal titanates was examined for their NOx sensing properties at elevated temperatures of 500-600℃. As a result, BaTiO3 and SrTiO3 sensors were found to be rather sensitive to NO and/or NO2 existing in air at 600 and 500℃, respectively, together with practically acceptable response and recovery rates. At these temperatures, both sensors exhibited almost linear sensitivity-NOx concentration correlations in the concentration range of 5-100ppm.The electrical resistance of SrTiO3 sensor at 500℃was almost independent of oxygen concentration in the range of 3-15％and scarcely affected by interfering gases such as CO2, H2, and C3H6. The NOx sensing mechanism of this element was briefly discussed.