Study of Hydrogen Peroxide Vapors Sensor Made of Nanostructured Co-doped SnO2 Film

A technology was developed for manufacturing the hydrogen peroxide vapors solid-state semiconductor sensor. Gas sensitive nanostructured films made of doped metal oxide SnO2 were manufactured by the high-frequency magnetron sputtering method. The chemical composition of prepared SnO2 targets was analyzed. The thickness of the deposited doped metal oxide film was measured. The morphology of the deposited Co-doped SnO2 film was studied by scanning electron microscopy. The sensor sensitivity to the different concentrations of hydrogen peroxide vapors was measured at different operating temperatures. It was found that the Co- doped SnO2 sensor exhibit a sufficient sensitivity to very low concentration of hydrogen peroxide vapors (875 ppb) at the operating temperature of 100 °C. It exhibits a sensitivity at low operating temperature (25 °C) when exposed to hydrogen peroxide vapors with a concentration greater than 3.5 ppm. The optimal performance was observed at the operating temperature of 150 °C. The sensor made of SnO2 had potential application in real samples for the implementation of medical diagnostic apparatus for use in determining low concentration of hydrogen peroxide vapors

Nanocomposite H2O2 Vapor Sensors Made on the Base of Carbon Nanotubes Covered with SnO2 Nanoparticles

In this work, we present the results of studies of the nanocomposite MWCNTs/SnO2 hydrogen peroxide vapor sensors. The technology of manufacturing these sensors has been developed. As a result of the measurements of the temperature characteristics, the 100 oC optimal operating temperature of the studied sensors has been found. The response and recovery curves of the sensors were investigated in the presence of different concentrations of hydrogen peroxide vapor in the atmosphere. Sufficiently high response when low concentrations of the target gas presents in the air is observed. The linear dependence of the sensors response on the concentration of hydrogen peroxide vapor is observed in a double logarithmic scale in a certain concentration range. The minimal registered gas concentration is 1 ppm or less than

Room Temperature Detection of Hydrogen Peroxide Vapor by Fe2O3:ZnO Nanograins

In this report, a Fe2O3:ZnO sputtering target and a nanograins-based sensor were developed for the room temperature (RT) detection of hydrogen peroxide vapor (HPV) using the solid-state reaction method and the radio frequency (RF) magnetron sputtering technique, respectively. The characterization of the synthesized sputtering target and the obtained nanostructured film was carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) analyses. The SEM and TEM images of the film revealed its homogeneous granular structure, with a grain size of 10–30 nm and an interplanar spacing of Fe2O3 and ZnO, respectively. EDX spectroscopy presented the real concentrations of Zn in the target material and in the film (21.2 wt.% and 19.4 wt.%, respectively), with a uniform distribution of O, Al, Zn, and Fe elements in the e-mapped images of the Fe2O3:ZnO film. The gas sensing behavior was investigated in the temperature range of 25–250 °C with regards to the 1.5–56 ppm HPV concentrations, with and without ultraviolet (UV) irradiation. The presence of UV light on the Fe2O3:ZnO surface at RT reduced a low detection limit from 3 ppm to 1.5 ppm, which corresponded to a response value of 12, with the sensor’s response and recovery times of 91 s and 482 s, respectively. The obtained promising results are attributed to the improved characteristics of the Fe2O3:ZnO composite material, which will enable its use in multifunctional sensor systems and medical diagnostic devices

Gas Sensor Based on ZnO Nanostructured Film for the Detection of Ethanol Vapor

In this paper, the ZnO target was synthesized by the solid-state reaction method and a nanostructured thin film was deposited by the RF (radio frequency) magnetron sputtering method on a Multi-Sensor-Platform. The obtained ZnO nanostructured film was investigated as the sensing material. Energy-Dispersive X-ray (EDX) analysis indicated the existence of La in the synthesized ZnO material. Scanning Electron Microscope (SEM) images of the film showed the grain sizes in the range of 20–40 nm. Sensor performance characteristics such as a dynamic response, response and recovery times, and ethanol detection range were investigated at 50–300 °C. A sensitivity was observed at extremely low concentrations of ethanol (0.7 ppm). The minimum response and recovery times of the sensor corresponding to 675 ppm ethanol vapor concentration at 250 °C were found to be 14 s and 61 s, respectively. The sensor showed a high response, good selectivity, fast response/recovery behavior, excellent repeatability toward ethanol vapor, and low sensitivity toward humidity. These characteristics enable the use of a ZnO based sensor for ethanol detecting applications

MWCNTs/Fe₂O₃:ZnO Nanocomposite Material for Chemoresistive Sensing of Hydrogen Peroxide Vapors

Hydrogen peroxide is widely used in medical and industrial applications, and the rapid detection of low concentrations of its vapor is considered to be a major challenge. In this study, we have successfully implemented the fabrication of an MWCNTs/Fe2O3:ZnO chemoresistive sensor for hydrogen peroxide vapor (HPV) detection using RF magnetron sputtering and electron-beam deposition methods. The material properties of the MWCNTs/Fe2O3:ZnO structure were characterized in detail using scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) elementary analysis, and transmission electron microscopy (TEM). The HPV sensing performances of the sensors were investigated in the temperature range 25–250 °C with and without ultraviolet (UV) irradiation. Sensor response values ranged from 35 to 1043 and from 7.3 to 198 at operating temperatures of 100 °C (without UV irradiation) and 150 °C (with UV irradiation), respectively, in the HPV concentration range of 1.5–22 ppm. Therefore, the Fe2O3:ZnO material decorated with MWCNTs is a promising candidate for integration into real-life HPV detection systems