Fluorescent nanoprobes for the sensing of gasotransmitters hydrogen sulfide (H2S), nitric oxide (NO) and carbon monoxide (CO) (original) (raw)
Related papers
p-CoOx/n-SnO2 nanostructures: New highly selective materials for H2S detection
Sensors and Actuators B: Chemical, 2017
Nanostructures p-CoO x /n-SnO 2 based on tin oxide nanowires have been prepared by two step CVD technique and characterized in detail by XRD, XRF, XPS, HAADF-STEM imaging and EDX-STEM mapping. Depending on the temperature of decomposition of cobalt complex during the second step of CVD synthesis of nanostructures cobalt oxide forms a coating and/or isolated nanoparticles on SnO 2 nanowire surface. It was found that cobalt presents in +2 and +3 oxidation states. The measurements of gas sensor properties have been carried out during exposure to CO (14 ppm), NH 3 (21 ppm), and H 2 S (2 ppm) in dry air. The opposite trends were observed in the effect of cobalt oxide on the SnO 2 gas sensitivity when detecting CO or NH 3 in comparison to H 2 S. The decrease of sensor signal toward CO and NH 3 was attributed to high catalytic activity of Co 3 O 4 in oxidation of these gases. Contrary, the significant increase of sensor signal in the presence of H 2 S was attributed to the formation of metallic cobalt sulfide and removal of the barrier between p-CoO x and n-SnO 2. This effect provides an excellent selectivity of p-CoO x /n-SnO 2 nanostructures in H 2 S detection.
Engineering Journal, 2012
The noxious gas sensors were developed successfully using flame-spray-made SnO2 nanoparticles as the sensing materials. The functionalized nanoparticle properties were further analyzed by XRD, BET and TEM analyses. The SnO2 nanoparticles (SSABET: 141.6 m 2 /g) were investigated revealing non-agglomerated spherical, hexagonal, rectangle (3-10 nm), and rod-like (3-5 nm in width and 5-20 nm in length) morphologies. The sensing films were prepared by spin coating onto the Al2O3 substrates interdigitated with Au electrodes. The sensing films were significantly developed in order to detect with H2S (0.5-10 ppm) and SO2 (20-500 ppm) at the operating temperature ranging from 200-350°C. After sensing test, the cross-section of sensing film was analyzed by SEM analyses. It was found that SnO2 sensing film showed higher sensitivity to H2S gas with very fast response at lower concentrations (3s, to 10 ppm). The cross sensitivities of the sensor towards different concentrations of H2S, CO, H2, and C2H2 were measured at 300°C. The sensor evidently shows much less response to CO, H2, and C2H2 than to H2S indicating higher selectivity for H2S of the SnO2 sensor at the lower concentration (10 ppm). Therefore, the SnO2 sensor was the most suitable candidate for the efficient detection of H2S noxious gas.
Nanomaterials-Based Resistive Sensors for Detection of Environmentally Hazardous H2S Gas
Journal of Electronic Materials, 2021
The development of nanomaterial-based gas sensors has led to demanding research interest in the last few decades due to their potential for high sensitivity, selectivity, and fast detection of various environmentally hazardous gases. Hydrogen sulfide (H 2 S) is a hazardous gas normally produced from sewage, mines, petroleum fields, gasoline, natural gas production, etc. In this review, advancements in the development of different metal-oxide semiconductors (MOS) and carbon-based H 2 S gas sensors are summarised. The commonly investigated materials in MOS are zinc oxide, tin oxide, tungsten oxide, titanium oxide, indium oxide, copper oxide, and composites, and in carbon allotropes, graphene, carbon nanotubes, and fullerene have been tested for H 2 S gas sensing. The main focus of this review is the description of the various synthesis processes and the morphology of H 2 S gas sensors by various researchers in order to improve the sensing performance parameters, such as response, sensitivity, selectivity, response time, and recovery time using different materials/catalysts.
Applications of Nanostructured Materials as Gas Sensors
Gas detection instruments are increasingly needed for industrial health and safety, environmental monitoring, and process control. To meet this demand, considerable research into new sensors is underway, including efforts to enhance the performance of traditional devices, such as resistive metal oxide sensors, through nano-engineering. The resistance of semiconductors is affected by the gaseous ambient. The semiconducting metal oxides based gas sensors exploit this phenomenon. Physical chemistry of solid metal surfaces plays a dominant role in controlling the gas sensing characteristics. Metal oxide sensors have been utilized for several decades for low-cost detection of combustible and toxic gases. Recent advances in nanomaterials provide the opportunity to dramatically increase the response of these materials, as their performance is directly related to exposed surface volume. Proper control of grain size remains a key challenge for high sensor performance. Nanoparticles of SnO 2 have been synthesized through chemical route at 5, 25 and 50 o C. The synthesized particles were sintered at 400, 600 and 800 o C and their structural and morphological analysis was carried out using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The reaction temperature is found to be playing a critical role in controlling nanostructure sizes as well as agglomeration. It has been observed that particle synthesized at 5 and 50 o C are smaller and less agglomerated as compared to the particles prepared at 25 o C. The studies revealed that particle size and agglomeration increases with increase in sintering temperature. Thick films gas sensors were fabricated using synthesized tin dioxide powder and sensing response of all the sensors to ethanol vapors was investigated at different temperatures and concentrations. The investigations revealed that sensing response of SnO 2 nanoparticles is size dependent and smaller particles display higher sensitivity.
Selective Detection of Nitrogen-Containing Compound Gases
Sensors, 2019
N-containing gaseous compounds, such as trimethylamine (TMA), triethylamine (TEA), ammonia (NH3), nitrogen monoxide (NO), and nitrogen dioxide (NO2) exude irritating odors and are harmful to the human respiratory system at high concentrations. In this study, we investigated the sensing responses of five sensor materials—Al-doped ZnO (AZO) nanoparticles (NPs), Pt-loaded AZO NPs, a Pt-loaded WO3 (Pt-WO3) thin film, an Au-loaded WO3 (Au-WO3) thin film, and N-doped graphene—to the five aforementioned gases at a concentration of 10 parts per million (ppm). The ZnO- and WO3-based materials exhibited n-type semiconducting behavior, and their responses to tertiary amines were significantly higher than those of nitric oxides. The N-doped graphene exhibited p-type semiconducting behavior and responded only to nitric oxides. The Au- and Pt-WO3 thin films exhibited extremely high responses of approximately 100,000 for 10 ppm of triethylamine (TEA) and approximately −2700 for 10 ppm of NO2, resp...
Fe-doped SnO 2 nanomaterial: A low temperature hydrogen sulfide gas sensor
Materials Chemistry and Physics, 2008
The effect of Fe-doping on the surface chemistry and gas-sensing properties of nanocrystalline tin oxide is analyzed. The pristine and Fedoped SnO 2 are synthesized by the modified Pechini citrate route that produces around 40 and 18 nm sized nanoparticles, respectively. 1 at.% Fe-doped SnO 2 shows significantly high selectivity towards hydrogen sulfide gas with capability to detect even 10 ppm of hydrogen sulfide at room temperature, with change of about one order of magnitude in the resistance within 5-15 s. In comparison, pristine SnO 2 shows negligible response towards H 2 S at room temperature. The ideal response and recovery of Fe-doped SnO 2 at low concentration of gas suggests Fe-doped SnO 2 nanomaterial as a potential low cost, low temperature H 2 S gas sensor.
Synthesis and use of a novel SnO2 nanomaterial for gas sensing
Applied Surface Science, 2000
bstract w Ž . x Decomposition of the organometallic precursor Sn NMe in a controlled waterranisol mixture leads to the 2 2 2 formation of monodisperse nanocomposite particles of SnrSnO . Full oxidation of the particles into SnO occurs at 6008C x 2 without size or morphology change. These particles can be deposited onto silicon nitride covered microelectronic platforms and used as sensitive layers of gas sensors. Doping of the sensors with palladium can be achieved either by co-decomposi-Ž . tion of organometallic precursors doping in volume or by deposition of palladium on preformed SnO nanoparticles 2 Ž
Semiconductor Metal Oxide Nanoparticles: A Review for the Potential of H2S Gas Sensor Application
Earthline Journal of Chemical Sciences, 2020
In modern world, gas sensors play important role in many fields of technology used for air pollution, breath analysis, public safety and many others. Gas sensor based semiconductor metal oxide is mostly used in these applications because of low cost, ease-to-use, high sensitivity and lower power consumption. This paper gives an overview about the semiconductor metal oxide and reviews why using it as sensing of gases in electrical applications and then it addresses to the work mechanism of a sensor to sensing H2S gas.