2D/0D SnSe2/TiO2 nanocomposites for trace NO2 detection under H2S interference at room temperature

Complex gas environments and the demand for room temperature detection will provide challenges for chemo-resistive-type gas sensors in a variety of applications. In this work, 2D/0D SnSe 2 /TiO 2 composite is used as a sensing material, displaying good sensitivity and specificity to ppb-level NO 2 at ambient temperature (25 °C). The response value and time of the SnSe 2 /TiO 2 sensor are 207 % and 139s when exposed to 100 ppb NO 2 , as opposed to 62 % and 183s for the pristine SnSe 2 sensor. The composite sensor also offers great long-term stability for NO 2 and good gas selectivity. Notably, the SnSe 2 /TiO 2 sensor's mixed gases (NO 2 +H 2 S) measurement is done to examine its NO 2 detection capacity in the presence of interfering gas. The constructed composite sensor can accurately detect NO 2 even if the concentration of the reductive interfering H 2 S is 66.7 times higher than that of the oxidative target NO 2 . The effective usage of SnSe 2 modified by TiO 2 for low-concentration, room-temperature NO 2 detection in a complex gas environment is shown by the composite sensor's pleasing gas detection results.