The XAFS spectra for the sensor. The labels
designate the following atmospheric conditions during X-ray interrogation. “Dark EtOH air” indicates a saturated ethanol atmosphere in darkness; “dark N2” indicates a nitrogen atmosphere in darkness; “light EtOH air” indicates a saturated ethanol atmosphere while the sensing surface is illuminated; “light EtOH N2” indicates a nitrogen atmosphere saturated with ethanol while the sensing surface is illuminated; “light N2” indicates a nitrogen atmosphere
while the sensing surface is illuminated; “light” indicates a dry air
atmosphere while the sensor is illuminated; and “sensor 2” indicates a dry air atmosphere while the sensor is kept in darkness. Figure 6(b) is the magnified X-ray
absorption near edge spectroscopy (XANES) portion of the spectra and describes
the valence state of Ti.
