Monitoring of hydrogen concentration using capacitive nanosensor in a 1% H ₂ –N ₂ mixture

Abstract

In this work, a hydrogen capacitor nanosensor with palladium nanoparticles (PdNPs) electrode based on metal-oxide-semiconductor structure has been fabricated. The capacitor sensor has been fabricated on the n-type silicon substrate with an oxide film thickness of 50 nm. PdNPs are synthesised and then deposited on the oxide surface using spin coating. PdNPs are characterised using by transmission electron microscope and UV spectrum. Also, the morphology of the oxide surface is characterised using by atomic force microscope. The response time and recovery time of nanosensor have been explained at the room temperature. The time interval to 90% of the signal value for 1% H 2-N 2 mixture was 1.4 s and recovery time was 14 s. The curve of pressure as a function of hydrogen concentration (H/Pd) in the PdNPs and the mechanism of the nanosensor are reported. The capacitor nanosensor based on nanoparticles shows sensitive and fast response.

Analysis of a calibration method for non-stationary CVD multi-layered graphene-based gas sensors

“…The limitations hereby discussed strongly impact two relevant parameters of the sensors, such as the response time and the percentage variation of the current induced by the analyte exposure. The response time is in fact the time required for reaching 90% of the steady-state signal magnitude [31,32].…”

Hierarchical WO3–NiO microflower for high sensitivity detection of SF6 decomposition byproduct H2S

“…The gas responses in this paper were defined as R g /R a , in which R g and R a were the sensor resistance in test gas and in air [44]. The response and recovery time in this work were counted as the time of response reached 90% of its maximum and fall to 10% of its maximum [48,49]. Itisnoteworthythat no other characteristic peaks belonging to tungsten have been observed from the results of WO 3 -NiO due to the relatively low introduction amount [37,50].…”

High-performance humidity sensor using Schottky-contacted SnS nanoflakes for noncontact healthcare monitoring

“…The current-voltage (I-V) measurements were taken from −1 V to +1 V and the resistance values were calculated from the slope of the plot through the least square method. The response (S%) of SnS nanoflakes-based humidity sensor is defined as the percent change in resistance [30][31][32][33][34]. S%=(ΔR/R x )× 100, where ΔR=(R dry -R x ), R dry and R x are the resistance of the sensor at dry air (3% RH) and x% RH, respectively.…”