Evaluation of response characteristics of resistive oxygen sensors using Ce0.9Zr0.1O2 thick film by pressure modulation method

Response properties of resistive oxygen sensors using zirconia-doped ceria (Ce0.9Zr0.1O2) thick film were investigated using the pressure modulation method (PMM). This method measures the amplitude of the output of an oxygen sensor under periodic changes in oxygen partial pressure. The PMM results revealed that the resistive oxygen sensor using our Ce0.9Zr0.1O2 thick film responds precisely when the oxygen partial pressure periodically changes at a period of 50 ms or more. The rate-limiting step of the response of the Ce0.9Zr0.1O2 thick film was the diffusion of oxygen vacancies. The diffusion coefficients (D) of the oxygen vacancies were calculated from the PMM results, and were determined almost the same as those for CeO2 thick films.