XPS characterization of xα-Fe2O3–(1−x)ZrO2 for oxygen gas sensing application

XPS characterization was carried out for the solid-solution xα-Fe2O3–(1−x)ZrO2 which is a potential low temperature oxygen gas sensing material. The significant variation of relative intensity of the two peaks in O 1s spectra provides us a unique way to estimate the oxygen vacancy concentrations of xα-Fe2O3–(1−x)ZrO2 with x ranging from 0 to 0.3. The estimation result from XPS coincides with the calculated values from the substitutional model. The relationship between the sensitivity of the fabricated oxygen gas sensor and the oxygen vacancy concentration in the sensing material was established.