Ambient Temperature Oxygen Sensors: Morphological Effects of PbSnF_4 Incorporated in the Sensing Electrode on Response

摘要

The size of the PbSnF_4 particles incorporated into the sensing electrode (SE) influences the response properties, particularly, the mean 90% response time t_(90)(m), of the amperometric oxygen sensor Ag|Ag_6I_4WO|PbSnF_4 (PSF)|SE (a mixture of SnO_2-coated 9Al_2O_3·2B_2O_3 whiskers, iron phthalocyanine, and PSF). With incorporation of the sheetlike PSF particles of ～ 18 μm as well as the conductive whiskers, the sensor responded unprecedentedly fast [t_(90)(m) ≈ 25 s] at room temperature, compared with t_(90)(m) for known solid-state electrochemical oxygen sensors. The results suggest that the SE mixture should be designed to realize fast response considering the dispersed state, which depends on the morphological feature of all the SE components.