RF sputtered SnO2: NiO thin films as sub-ppm H2S sensor operable at room temperature

Advances in designs and mechanisms of semiconducting metal oxide nanostructures for high-precision gas sensors operated at room temperature

“…112 The aim of this topical review is to critically evaluate the design and structure of SMON-based gas sensors that may help guide the design of new devices. The performance of these SMON based gas sensors operated at RT could be improved significantly by modifying the SMONs using noble metal nanoparticles, [113][114][115][116] metal ions, [117][118][119] composites of multiple SMONs [120][121][122][123] and carbon nanomaterials. [124][125][126] In addition, not only the quantity of chemisorbed oxygen species, 127 defects 128 and element compositions 129,130 on the surface of SMONs, but also the structural properties, i.e., porosity, 131 heterojunction properties [132][133][134] and conductivity 135,136 can affect the RT gas sensing performance.…”

“…The mesoporous hierarchical nanostructures with much larger surface areas facilitate effective adsorption and desorption of gas molecules on the surface. Thus, the sensor exhibits an ultra-fast response speed (2 s to 100 ppm NO 2 ) to NO 2 at RT.Kaur et al123 prepared a SnO 2 /NiO thin film using a sputtering method and then fabricated a RT H 2 S sensor. As shown in…”

A fast response and recovery H2S gas sensor based on free-standing TiO2 nanotube array films prepared by one-step anodization method

“…The changing process of oxygen molecules on the nanotube surface is illustrated in Eqs. (1)(2)(3)(4) [38,39]:…”

“…Hydrogen sulfide (H 2 S) is one of the main pollutants produced in various industrial processes. It is colorless, highly toxic, extremely flammable and corrosive in nature [1,2]. Humans exposed to H 2 S at low concentrations suffer eye irritation, olfactory fatigue, and damage to the lungs and nervous system.…”

An effective H2S sensor based on SnO2 nanowires decorated with NiO nanoparticles by electron beam evaporation

“…22,23 The p-type NiO is highly reactive with H 2 S, that is, H 2 S can convert NiO into NiS; 24 thus, this material is currently used to decorate or functionalise SnO 2 to enhance its H 2 S-sensing performance. 25 Several researchers have studied the decoration of SnO 2 nanomaterials by NiO nanoparticles to enhance their gas sensing performance. 26 Lee et al 27 reported the improvement of H 2 S sensing properties of thick-lm SnO 2based gas sensors by surface decoration with NiO and MoO 3 nanoparticles.…”