Tuning SnO 2 architectures with unitary or composite microstructure for the application of gas sensors

Facile Synthesis of Hierarchical Tin Oxide Nanoflowers with Ultra-High Methanol Gas Sensing at Low Working Temperature

“…From Fig. 5a–e, it is clearly seen that the as-synthesized HTONF samples annealed at 400 °C show the biggest surface area (35.678 m 2 /g), which provides the biggest number of active sites and improves the gas sensitivity performance of the HTONF [30, 31]. In our opinion, the changes in specific surface area are part of a complex process of phase transformation accompanied with growth of nanostructures of different shapes such as leaves, needles, membranes, etc.…”

Hollow WO3/SnO2 Hetero-Nanofibers: Controlled Synthesis and High Efficiency of Acetone Vapor Detection

“…The binding energy of Sn 3d 3/2 (494.98 eV) and Sn 3d 5/2 (486.58 eV) in particular, are displayed in the pure SnO 2 , but a minor negative shift of 0.18 eV can be noted for the Sn 3d 3/2 (494.8 eV) and Sn 3d 5/2 (486.4 eV) in the WO 3 /SnO 2 (0.3%) composite (Figure 5B) (Lavacchi et al, 2000; Liu et al, 2016). Furthermore, a minor negative shift of the binding energy is also observed for the element of O 1s (Figure 5C), i.e., the lattice oxygen [530.38 eV (O I )] and chemisorbed oxygen (531.24 eV (O II )) for pure SnO 2 , while 530.38 eV (O I ) and 531.11 eV (O II ) are the values for the WO 3 /SnO 2 (0.3%) composite, wherein the chemisorbed oxygen of O II shifts negatively for 0.13 eV (Yang and Guo, 2016; Yang C. et al, 2019). Note that the gas sensing property is quite relative to the content of chemisorbed oxygen which increases by 9% after W modification, so the sensing performance would be remarkably improved (Teng et al, 2019).…”

“…Thus, the electron concentration will be reduced to form an electron depletion layer, resulting in a higher resistance. When the sensor is exposed to the reduced gas like acetone, it can react with the adsorbed O − and release the captured electrons back, thus decreasing the resistance (Das and Jayaraman, 2014; Yang and Guo, 2016).…”

“…To date, a great deal of research still focuses on fabricating high performance metal oxide semiconductor (MOS) gas sensing materials due to their many irreplaceable advantages such as their stability and their reliable sensing (Kucheyev et al, 2006; Das and Jayaraman, 2014; Yang and Guo, 2016; Teng et al, 2019), especially in improving the gas sensing properties of SnO 2 -based nanomaterials through the assembly into heterojunctions (Das and Jayaraman, 2014; Koohestani, 2019; Teng et al, 2019). It is known that pristine SnO 2 -based sensors often work at higher temperatures (>300°C) with poor selectivity, a lack of reproducibility, and an inadequate detection limit, thereby restricting their practical application (Wang et al, 2016; Wang L. et al, 2019).…”

Preparation of reduced graphene oxide/Co3O4 composites and sensing performance to toluene at low temperature

“…1,2 Therefore, the development of a reliable and sensitive as well as highly selective toluene sensor has become imperative. 3 Up to now, the sensors based on the ntype semiconductor oxides, such as SnO 2 , ZnO, TiO 2 , WO 3 and etc., [4][5][6][7] have been widely used to detect toxic gases due to their structure simple, facile integration, cost-efficiency and potential sensing performance to some of toxic reducing gases and oxidizing gases. 8 In contrast, the research and fabrication of sensors based on p-type oxide semiconductors, such as NiO, CuO, Co 3 O 4 and Cr 2 O 3 , to date are still in the early stages of development.…”