Detection of 2-ethyl hexanol and dioctyl phthalate with potentiometric sensor based on ordered ZnO nanorods sensing electrode

Abstract

In this work, a planar mixed-potential sensor was prepared by in situ growth of ZnO nanorods sensing electrode on yttria-stabilized zirconia (YSZ) electrolyte. The potentiometric sensing properties of the sensor toward two signature gases of early PVC cable fires, 2-ethyl hexanol (2-EH) and dioctyl phthalate (DOP), were studied. High response values of −205.1 mV and −54.1 mV were achieved at 400 °C for ∼171–193 ppm 2-EH and ∼89–109 ppt DOP for ZnO nanorods-based sensor, which were 1.7 and 4.1 times higher than those of ZnO nanoparticles-based sensor, respectively. Furthermore, ZnO nanorods exhibited much better 2-EH and DOP selectivity. The improvement of the gas-sensing performance of ZnO nanorods may be ascribed to the unique three-dimensional electrode morphology.