scholarly journals Synthesis of ZnO-CuO flower-like hetero-nanostructures as volatile organic compounds (VOCs) sensor at room temperature

2018 ◽  
Vol 36 (3) ◽  
pp. 452-459
Author(s):  
Raad S. Sabry ◽  
Roonak Abdul Salam A. Alkareem
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Room Temperature ◽  
Dip Coating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Volatile Organic ◽  
Recovery Times ◽  
Coating Methods ◽  
Response And Recovery

AbstractZnO-CuO flower-like hetero-nanostructures were successfully prepared by combining hydrothermal and dip coating methods. Flower-like hetero-nanostructures of ZnO-CuO were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and UV-Vis. The sensing properties of ZnO-CuO flower-like hetero-nanostructures to volatile organic compounds (VOCs) were evaluated in a chamber containing acetone or isopropanol gas at room temperature. The sensitivity of ZnO-CuO flower-like hetero-nanostructures to VOCs was enhanced compared to that of pure leafage-like ZnO nanostructures. Response and recovery times were about 5 s and 6 s to 50 ppm acetone, and 10 s and 8 s to 50 ppm isopropanol, respectively. The sensing performance of ZnO-CuO flower-like hetero-nanostructures was attributed to the addition of CuO that led to formation of p-n junctions at the interface between the CuO and ZnO. In addition, the sensing mechanism was briefly discussed.

Fabrication of TiO2 sensor using rapid breakdown anodization method to measure pressure, humidity and sense gases at room temperature

2019 ◽  
pp. 1694-1703
Author(s):  
Reem Saadi Khaleel ◽  
Mustafa Shakir Hashim
Keyword(s):  
Room Temperature ◽  
Average Pressure ◽  
Spherical Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Recovery Times ◽  
Sensitivity And Selectivity ◽  
Response And Recovery ◽  
Anodization Method ◽  
Rapid Breakdown Anodization

Rapid breakdown anodization (RBA) process was used to fabricate TiO2 sensor to measure pressure and humidity and sense gases at room temperature. This chemical process transformed Ti to its oxide (TiO2) as a powder with amorphous phase as X ray diffraction (XRD) technique confirmed.  This oxide consisted from semi spherical nanoparticles and titania nanotubes (TNTs) as Scanning electron microscope (SEM) technique showed.  TiO2 powder was deposited on Ti substrates by using electrophoretic deposition (EPD) method.   Average pressure sensitivity was 0.34 MΩ/bar and hysteresis area was 1.4 MΩ .bar. Resistance of TiO2 decreased exponentially with the increasing of relative humidity (RH%). The sensitivity% of TiO2 for RH% was greater than 70% in the range of (50-95). TiO2 was tested as a sensor for Ammonia, Ethanol and Methanol. Its sensitivity and selectivity towards Ammonia were the greatest but the shortest response and recovery times were recorded toward Methanol.

Silicon Carbide Field Effect Transistors for Detection of Ultra-Low Concentrations of Hazardous Volatile Organic Compounds

2014 ◽  
Vol 778-780 ◽  
pp. 1067-1070 ◽  
Author(s):  
Donatella Puglisi ◽  
Jens Eriksson ◽  
Christian Bur ◽  
Andreas Schütze ◽  
Anita Lloyd Spetz ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Volatile Organic Compounds ◽  
Relative Humidity ◽  
Organic Compounds ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Long Term Stability ◽  
Volatile Organic ◽  
Recovery Times ◽  
Response And Recovery

Gas sensitive silicon carbide field effect transistors with nanostructured Ir gate layers have been used for the first time for sensitive detection of volatile organic compounds (VOCs) at part per billion level for indoor air quality applications. Formaldehyde, naphthalene, and benzene have been used as typical VOCs in dry air and under 10% and 20% relative humidity. A single VOC was used at a time to study long-term stability, repeatability, temperature dependence, effect of relative humidity, sensitivity, response and recovery times of the sensors.

scholarly journals Time-lapse synchrotron X-ray diffraction to monitor conservation coatings for heritage lead in atmospheres polluted with oak-emitted volatile organic compounds

2014 ◽  
Vol 82 ◽  
pp. 280-289 ◽  
Author(s):  
Rosie Grayburn ◽  
Mark Dowsett ◽  
Michel De Keersmaecker ◽  
Eric Westenbrink ◽  
James A. Covington ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Time Lapse ◽  
X Ray Diffraction ◽  
X Ray ◽  
Volatile Organic

scholarly journals Silver Enhances Hematite Nanoparticles Based Ethanol Sensor Response and Selectivity at Room Temperature

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 440
Author(s):  
Daniel Garcia-Osorio ◽  
Pilar Hidalgo-Falla ◽  
Henrique E. M. Peres ◽  
Josue M. Gonçalves ◽  
Koiti Araki ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Gas Sensors ◽  
Room Temperature ◽  
Gas Sensing ◽  
Ethanol Vapor ◽  
Oxide Semiconductor ◽  
Charge Carrier Density ◽  
Ethanol Sensor ◽  
Volatile Organic

Gas sensors are fundamental for continuous online monitoring of volatile organic compounds. Gas sensors based on semiconductor materials have demonstrated to be highly competitive, but are generally made of expensive materials and operate at high temperatures, which are drawbacks of these technologies. Herein is described a novel ethanol sensor for room temperature (25 °C) measurements based on hematite (α‑Fe2O3)/silver nanoparticles. The AgNPs were shown to increase the oxide semiconductor charge carrier density, but especially to enhance the ethanol adsorption rate boosting the selectivity and sensitivity, thus allowing quantification of ethanol vapor in 2–35 mg L−1 range with an excellent linear relationship. In addition, the α-Fe2O3/Ag 3.0 wt% nanocomposite is cheap, and easy to make and process, imparting high perspectives for real applications in breath analyzers and/or sensors in food and beverage industries. This work contributes to the advance of gas sensing at ambient temperature as a competitive alternative for quantification of conventional volatile organic compounds.

scholarly journals Catalytic Abatement of Volatile Organic Compounds and Soot over Manganese Oxide Catalysts

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4534
Author(s):  
Miguel Jose Marin Figueredo ◽  
Clarissa Cocuzza ◽  
Samir Bensaid ◽  
Debora Fino ◽  
Marco Piumetti ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Low Temperature ◽  
Manganese Oxide ◽  
Organic Compounds ◽  
Catalytic Performance ◽  
Oxide Catalysts ◽  
X Ray ◽  
Manganese Oxide Catalysts ◽  
Volatile Organic ◽  
Temperature Programmed

A set of manganese oxide catalysts was synthesized via two preparation techniques: solution combustion synthesis (Mn3O4/Mn2O3-SCS and Mn2O3-SCS) and sol-gel synthesis (Mn2O3-SG550 and Mn2O3-SG650). The physicochemical properties of the catalysts were studied by means of N2-physisorption at −196 °C, X-ray powder diffraction, H2 temperature-programmed reduction (H2-TPR), soot-TPR, X-ray photoelectron spectroscopy (XPS) and field-emission scanning electron microscopy (FESEM). The high catalytic performance of the catalysts was verified in the oxidation of Volatile Organic Compounds (VOC) probe molecules (ethene and propene) and carbon soot in a temperature-programmed oxidation setup. The best catalytic performances in soot abatement were observed for the Mn2O3-SG550 and the Mn3O4/Mn2O3-SCS catalysts. The catalytic activity in VOC total oxidation was effectively correlated to the enhanced low-temperature reducibility of the catalysts and the abundant surface Oα-species. Likewise, low-temperature oxidation of soot in tight contact occurred over the Mn2O3-SG550 catalyst and was attributed to high amounts of surface Oα-species and better surface reducibility. For the soot oxidation in loose contact, the improved catalytic performance of the Mn3O4/Mn2O3-SCS catalyst was attributed to the beneficial effects of both the morphological structure that—like a filter—enhanced the capture of soot particles and to a probable high amount of surface acid-sites, which is characteristic of Mn3O4 catalysts.

Synergistic effect of ZnO/ZIF8 heterostructure material in photodegradation of methylene blue and volatile organic compounds with sensor operating at room temperature

2020 ◽  
Vol 289 ◽  
pp. 121494
Author(s):  
Jiraporn Buasakun ◽  
Phakinee Srilaoong ◽  
Gun Chaloeipote ◽  
Ramida Rattanakram ◽  
Chatchawal Wongchoosuk ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Volatile Organic Compounds ◽  
Synergistic Effect ◽  
Organic Compounds ◽  
Room Temperature ◽  
Volatile Organic

scholarly journals A superhydrophobic hyper-cross-linked polymer synthesized at room temperature used as an efficient adsorbent for volatile organic compounds

RSC Advances ◽  
2016 ◽  
Vol 6 (99) ◽  
pp. 97048-97054 ◽  
Author(s):  
Junhui Wang ◽  
Wan-Qiu Wang ◽  
Zhengping Hao ◽  
Gang Wang ◽  
Yang Li ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Surface Area ◽  
Organic Compounds ◽  
Room Temperature ◽  
Large Surface Area ◽  
High Adsorption ◽  
Volatile Organic ◽  
Efficient Adsorbent

The hyper-cross-linked polymers CLBE-xwere prepared at room temperature and exhibit a large surface area, super-hydrophobicity and high adsorption for benzene.

X-ray diffraction analysis for thin films of PbTiO3-La2/3TiO3 prepared by the sol-gel method

1994 ◽  
Vol 9 (8) ◽  
pp. 2133-2137 ◽  
Author(s):  
Hideki Yoshioka
Keyword(s):  
Thin Films ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Diffraction Method ◽  
Dip Coating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coating Methods ◽  
Diffraction Patterns ◽  
System 1

Thin films in the system (1 - x) PbTiO3−xLa2/3TiO3 were prepared by the sol-gel and dip-coating methods. Phases deposited in the films and the lattice parameters as a function of the composition were investigated by the x-ray diffraction method. The solid solutions with a perovskite structure were formed as a single phase with x up to 0.9. For the composition of x = 1.0, metastable La-Ti-O perovskite phase with a small amount of the impurity phase, La2Ti2O7, was obtained. Simulation of x-ray diffraction patterns based on the defect structure model shows that the structure of the La-Ti-O perovskite phase includes randomly distributed cation vacancies at the A-site, namely (La2/3□1/3)TiO3.

Sign in / Sign up

Export Citation Format

Share Document