2D SnSe2 nanoflakes decorated with 1D ZnO nanowires for ppb-level NO2 detection at room temperature

Dual Improvement in Sensitivity and Humidity Tolerance of a NO2 Sensor Based on 3-Aminopropyltriethoxysilane Self-Assembled Monolayer-Functionalized SnSe2 for Explosive Photolysis Gas Detection

“…Since Sn 4+ is present in the prepared samples and no other valence states are available, the peaks at 494.8 and 486.3 eV can be attributed to Sn 3d 3/2 and Sn 3d 5/2 , respectively . The peaks at 54.7 and 53.9 eV in Figure h are Se 3d 3/2 and Se 3d 5/2 , respectively, and they have distinctive peaks of Se 2‑ Figure i shows the presence of the C 1s peaks in the AS0 and AS3 samples, where CO, C–O, and C–C are represented by peaks at 289.2, 285.9, and 284.8 eV, respectively.…”

“…Layered metal dichalcogenides (LMDs), a kind of two-dimensional (2D) materials, have gained significant interest from academics due to their substantial specific surface area and high carrier mobility, which offer LMDs a wealth of active sites for gas adsorption and direct electron transfer with target gas molecules, resulting in room-temperature sensing characteristics. , Among various LMDs, tin diselenide (SnSe 2 ) has unique selectivity to NO 2 due to the stronger adsorption energy to NO 2 molecules than other gas molecules, − facilitating its utilization in the detection of photolysis gases of nitro explosives. On the other hand, sensors made from pristine SnSe 2 typically have a limited response and incomplete recovery . Some reported techniques for improving the performance of gas sensors based on SnSe 2 include heterojunction construction, noble metal modification, and elemental doping .…”

Indium-doping-induced selenium vacancy engineering of layered tin diselenide for improving room-temperature sulfur dioxide gas sensing

“…Owing to the limited number of water molecules at the low RH level, the pre-adsorbed water molecule content is relatively low, and the water molecules can be driven by the adsorbed SO 2 molecules, resulting in a larger response. 15 When the RH level increases (40–80% RH), the active sites of materials will be fully occupied by water molecules. At this stage, competition between water molecules and SO 2 molecules dominates, leading to a decreased gas response.…”

“…The deconvoluted peak at 533.3 eV (green) can be assigned to adsorbed oxygen, implying that oxygen can pre-adsorb on the surface of materials. 15 It can be inferred that SO 2 will react with adsorbed oxygen while also directly transferring electrons to the materials. When the SO 2 concentrations are low, SO 2 will mostly react with pre-adsorbed oxygen, resulting in a significant response discrepancy.…”

“…13,14 Moreover, LMDs also have inherent 2D material properties such as high surface-to-volume ratios and carrier mobility, resulting in more exposed edge active sites and quicker electron transfer rates. 15,16 These features of LMDs have been used by some researchers to construct room-temperature SO 2 sensors. Zhang et al used a self-assembly technique to make Pt loaded TiO 2 /MoS 2 nanohybrids.…”