Sensitive, selective and stable tin dioxide thin-films for carbon monoxide and hydrogen sensing in integrated gas sensor array applications

Gas Sensing Characteristics of Nanocrystalline Ba0.5Sr0.5MoO4 Thick Film Prepared by Sol-Gel Method

“…Also, the thermal desorption of the target gas molecules from the sensitive surface at higher temperatures becomes more significant and hinders the solidgas interaction required for carrier generation. (29) Hence, it is important to find the maximum sensitivity temperature for the sample devices fabricated. In Fig.…”

Optical sensor for pH monitoring using a layer-by-layer deposition technique emphasizing enhanced stability and re-usability

“…Ionic strength, pH, concentration of the polyion solutions and the presence of a copolymer such as salt affect the LbL assembly, the film thickness and its stability [2,3]. Heat treatment is also an important process which has been discussed in many works in the literature [10][11][12] to achieve a higher stability of the thin films and avoid problems with the destruction of the films when they are immersed in buffer solutions of different values of pH [13,14]. However this sort of treatment affects the sensor performance and decreases its sensitivity [14], as well as allowing for a degradation of the indicator dyes used which happens at high temperatures.…”

“…Liu et al also used a silica nanoparticle layer on top of further layers of indium oxide nanoparticles and poly(styrene sulfonate) (PSS) as an insulating layer, in the approach published in [30]. Selectivity for hydrogen gas was obtained by deposition of a thin film of silica nanoparticles on top of the SnO 2 ±Cu/Pt, in a mixture of the two gases [10].…”

Biasing Voltage Dependence of Sensitivity of Electron Beam Evaporated SnO2 Thin Film CO Sensor

“…Tin oxide based semiconductor gas sensors have been widely used for detection of the environmentally hazardous pollutant gases in general and carbon monoxide gas in particular [1][2][3][4][5][6]. However their detecting mechanism is not fully yet established.…”

“…However their detecting mechanism is not fully yet established. Film parameters that are widely known to affect the sensing properties of a thin film are surface roughness, stoichiometry, grain size, structure (amorphous or polycrystalline), and porosity [1][2][3][4][5][6]. Furthermore depending on the preparation conditions of the sensing layers (physical vapor deposition, chemical vapor deposition, screen-printed and sintered materials) and also on the sensor design (nature and geometry of the electrodes), large differences of behavior concerning gas response and selectivity are observed [7][8][9].…”