Oxygen Sensing by Electrochemical Pumping

A high temperature O₂ sensor is described based on electrochemical pumping with a ceramic structure incorporating two ZrO₂ O₂ concentration cells. Two modes of operation, steady state and oscillatory, are described. In each case at least a linear sensitivity to ambient O₂ concentration can be achieved. A potential application is that of exhaust-gas O₂ sensing for the feedback control of intake air-to-fuel ratios at values lean of stoichiometry.