Improved recovery time and sensitivity to H2 and NH3 at room temperature with SnOx vertical nanopillars on ITO

Abstract

Nanostructured SnO2 is a promising material for the scalable production of portable gas sensors. To fully exploit their potential, these gas sensors need a faster recovery rate and higher sensitivity at room temperature than the current state of the art. Here we demonstrate a chemiresistive gas sensor based on vertical SnOx nanopillars, capable of sensing < 5 ppm of H2 at room temperature and 10 ppt at 230 °C. We test the sample both in vacuum and in air and observe an exceptional improvement in the performance compared to commercially available gas sensors. In particular, the recovery time for sensing NH3 at room temperature is more than one order of magnitude faster than a commercial SnO2 sensor. The sensor shows an unique combination of high sensitivity and fast recovery time, matching the requirements on materials expected to foster widespread use of portable and affordable gas sensors.

Ammonia Gas Sensing Behavior of Hybridization between Reduced Graphene Oxide and Gold Nanoparticles

“…The surface plasmon resonance peak in the stack sample appears at 520 nm, indicating that the as-synthesized AuNP size is around 20 nm. The features of UV-Vis absorption spectra are consistent with the characteristics of AuNPs reported on Cytodiagnostics and NanoComposix websites [16,17], and in agreement with what we observed from the TEM image. Specifically, the surface plasmon resonance peak of the composite sample is shifted to 610 nm with a stronger intensity in comparison to the stack sample.…”

“…According to reports of Osorio-Arrieta et al and D'Arsié et al, the t 1 and t 2 values in sensors may be related to different interactions of the NH 3 molecules with the sensing layer. The fast phenomena (the short time t 1 ) can arise in adsorption of gas molecules onto the sensing film surface; meantime, the quite slow phenomena (the long time t 2 ) can be originated from a diffusion of NH 3 molecules into the sensing film [17,20]. Also, the interaction of the NH 3 molecules with adsorbed oxygen species is weaker than the interaction of the NH 3 molecules with sp 3 -hybridized carbon atoms.…”

Fe3O4 Nanoparticle-Decorated WSe2 Nanosheets for Selective Chemiresistive Detection of Gaseous Ammonia at Room Temperature

“…The search includes all TMDs, metal oxide composites with polymers, or RGO and TMD/metal oxide composites. It can be clearly seen from Figure that our sensor is superior to most of the already reported works in the literature in the scale of lowest limit of detection. ,,,,,− The detailed comparison with respect to other sensing metrics is listed in Table S1.…”

Facile Fabrication of Hybrid Carbon Nanotube Sensors by Laser Direct Transfer

“…For the last 50 years, the field of sensors has been dominated by the metal oxide semiconductor sensors (MOS) based on SnO2, In2O3, ZnO2, WO3, etc. [5]. This type of sensors have numerous advantages in terms of raw material costs, high sensitivity, etc..…”