SENSOR FOR DETECTING PLURAL GASES AND ITS PREPARATION AND GAS COMPONENT CONCENTRATION DETECTION APPARATUS USING SAID SENSOR AND SEPARATING PLURAL GASES TO DETECT THE SAME

摘要

PURPOSE:To obtain a sensor having novel characteristics, by such a simple method that a platinum electrode is formed to one surface of an oxygen ion conductor while an anode to the opposed surface thereof and the cathode is coated with a porous layer and subsequently heat-treated at predetermined temp. to make the activity of the cathode to carbon dioxide lower than that to steam. CONSTITUTION:A sensor consists of an oxygen ion conductor 1, a platinum cathode 2, an anode 3, a porous layer 4, a protective layer 5 and a platinum wire 6 and is heat-treated at 750-900 deg. to make the activity of the cathode to carbon monoxide lower than that to steam. The output of a first voltage setting part 3 is applied to the sensor by a change-over part 6 and the output current thereof is detected by a current detection part 7 while the detected value is applied to a first sample hold part 8 to output the signal to the concn. of O2 from output A. Similarly, outputs of second and third voltage setting parts 4, 5 are applied and the detection signals thereof receive operational processing by first and second operation parts 11, 12 and the signals to the concns. to H2O and CO2 are respectively outputted from output terminals B, C.