Determination of the sensing properties of the fluorescence-based sensor for atmospheric NO₂ gas

Air pollution in urban areas poses a serious threat to human health and therefore the studies about the development of low cost and sensitive sensors to monitor the air quality with high spatial and low temporal resolution continue to be an extensive area in literature. In this study, oxime modified poly(4-(1-pyrenyl) styrene) (P(PySt)-NOX) probes were synthesized to use as a sensor to detect NO₂ gas in ambient air. The structural characterization results showed that the probe was successfully synthesized. The sensitivity, selectivity, repeatability, and aging tests were performed during the study, and it was observed that P(PySt)-NOX loaded sensor is sensitive to NO₂ for concentrations below 100 ppb. The selectivity measurements were performed against O₃ and SO₂ which are common interfering gases in ambient air, and it was shown that the sensor is selective to NO₂. Additionally, according to the aging tests performed in laboratory for 23 days, it was observed that the sensor is stable in this time interval. The studies showed the sensor synthesized and designed in this study is suitable for NO₂ concentration measurements in ambient air where the concentration levels of NO₂ is below 100 ppb.