NO2 gas sensing properties of Au-functionalized porous ZnO nanosheets enhanced by UV irradiation

Two-Dimensional Zinc Oxide Nanostructures for Gas Sensor Applications

“…The superior gas-sensing performance of flower-like ZnO was attributed to the higher oxygen vacancies and the morphology maintained after sensor preparation, which provides a higher surface for the gas adsorption. Mun et al [75] synthesized Au-decorated ZnO nanosheets using a three-step process consisting of ZnO fabrication by a thermal evaporation of Zn powder, Au sputter deposition, and thermal annealing at 700 °C. For the fabrication of the sensor, Ni and Au thin films were deposited by sputtering to form interdigitated electrodes on a silicon substrate, then ZnO nanosheets suspended in ethanol were poured on the electrodes.…”

“…The significant enhancement in the response of the ZnO nanosheets to NO2 gas by UV irradiation was attributed to the increased change in resistance due to the photogeneration of electrons and holes. Mun et al [75] synthesized Au-decorated ZnO nanosheets using a three-step process consisting of ZnO fabrication by a thermal evaporation of Zn powder, Au sputter deposition, and thermal annealing at 700 • C. For the fabrication of the sensor, Ni and Au thin films were deposited by sputtering to form interdigitated electrodes on a silicon substrate, then ZnO nanosheets suspended in ethanol were poured on the electrodes. The sensing performances towards 1-5 ppm NO 2 at room temperature, and under 365 nm UV irradiation, were investigated.…”

Thickness and UV irradiation effects on the gas sensing properties of Te thin films

“…Comini et al [16] have shown that exposure of UV radiation results in decrease in the response and recovery time of tin oxide gas sensor at low temperature with no poisoning effect when NO 2 come in contact. Mun et al [17] have shown a significant enhancement in the response of the ZnO nanosheets to NO 2 gas by UV irradiation which was attributed to the increase in resistance due to the photo-generation of electrons and holes. So far, the effect of UV irradiation on the sensitivity of Te-based sensors has not been investigated.…”

ZnO Quasi-1D Nanostructures: Synthesis, Modeling, and Properties for Applications in Conductometric Chemical Sensors

“…In recent years, ZnO quasi-1D nanostructures have been functionalized with the noble catalytic metals (Au, Pd, and Ag) mainly in the shape of nanoparticles [40][41][42]. Au is the most used catalyzer among the noble metals according to reported studies [40,[43][44][45]. Au nanoparticles with uniform dispersion can be loaded using Chloroauric acid (HAuCl4) as the precursor [43,44].…”

“…Au nanoparticles with uniform dispersion can be loaded using Chloroauric acid (HAuCl 4 ) as the precursor [43,44]. Direct current (DC) sputtering is another technique for the functionalization of ZnO nanostructures with the homogeneous distribution of the Au nanoparticles [40,45]. The loading of Pd nanoparticles is performed using a solution of PdCl 2 [41].…”