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

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.

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

Materials ◽

10.3390/ma14164534 ◽

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.

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Selective adsorption of chlorinated volatile organic compound vapours by microcrystalline 1D coordination polymers

Dalton Transactions ◽

10.1039/c6dt03803d ◽

2016 ◽

Vol 45 (47) ◽

pp. 18832-18837 ◽

Cited By ~ 9

Author(s):

Massimo Cametti ◽

Javier Martí-Rujas

Keyword(s):

Organic Compound ◽

Organic Compounds ◽

Coordination Polymers ◽

Volatile Organic Compound ◽

Selective Adsorption ◽

X Ray Diffraction ◽

X Ray ◽

Chlorinated Volatile Organic Compounds ◽

H Nmr ◽

Volatile Organic

Microcrystalline 1D coordination polymers 1–3Pwd are able to adsorb vapours of chlorinated volatile organic compounds (Cl-VOCs), displaying interesting selectivity patterns, as demonstrated by 1H-NMR and X-ray diffraction analyses.

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Hydrophobic Porous Benzene-Silica Hybrid Clay Heterostructure and Its Application in the Adsorption of Volatile Organic Compounds

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.470 ◽

2006 ◽

Vol 514-516 ◽

pp. 470-474 ◽

Cited By ~ 8

Author(s):

P. Ferreira ◽

C.D. Nunes ◽

João Pires ◽

Ana P. Carvalho ◽

P. Brandão ◽

...

Keyword(s):

Electron Microscopy ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Thermal Analyses ◽

Nitrogen Adsorption ◽

X Ray Diffraction ◽

Organic Precursor ◽

Transmission Electron ◽

Volatile Organic ◽

Silica Hybrid

A new porous benzene-silica hybrid clay heterostructure has been prepared by a template-assisted method. The synthesis of Hybrid Porous Clay Heterostructures (HPCH) has been performed via the intercalation of a quaternary ammonium cation surfactant (cetyltrimethylammonium bromide) and a neutral amine (octylamine) as cosurfactant, in a Portuguese clay, to direct the interlamellar hydrolysis and condensation polymerisation of neutral inorganic etraethylorthosilicate (TEOS) together with an organic precursor, the 1,4- bis(triethoxysilyl)benzene (BTEB). The material has been characterised by elemental analysis, powder X-ray diffraction, nitrogen adsorption, 13C CP MAS, 29Si MAS and CP MAS NMR spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermal analyses. The hydrophobicity of the material was tested by water adsorption. Its potential application as adsorbent of volatile organic compounds was studied by the adsorption of methanol, methyl ethyl ketone, toluene and trichloroethylene.

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Synthesis and Characterization of TiO2 Nanotubes (TiO2-NTs) Decorated with Platine Nanoparticles (Pt-NPs): Photocatalytic Performance for Simultaneous Removal of Microorganisms and Volatile Organic Compounds

Materials ◽

10.3390/ma14237341 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7341

Author(s):

Lotfi Khezami ◽

Imen Lounissi ◽

Anouar Hajjaji ◽

Ahlem Guesmi ◽

Aymen Amine Assadi ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Tio2 Nanotubes ◽

Diffuse Reflectance Spectroscopy ◽

Bacterial Inactivation ◽

X Ray Diffraction ◽

Simultaneous Treatment ◽

Volatile Organic ◽

Tio2 Nts

This work reports on the effect of TiO2 nanotubes (TiO2-NTs), decorated wih platinum nanoparticles (Pt-NPs), on the removal of bacteria and volatile organic compounds (VOCs). The Pt-NPs were loaded onto the TiO2-NTs using the electrodeposition method at four decoration times (100, 200, 300, and 600 s). The realized Pt-NPs/TiO2-NTs nanocomposites were used for the degradation of cyclohexane, a highly toxic and carcinogenic VOC pollutant in the chemical industry. The achieved Pt-NPs/TiO2-NTs nanocomposites were characterized using X-ray diffraction (XRD), photoluminescence (PL), diffuse reflectance spectroscopy (UV–Vis), and scanning (SEM) and transmission (TEM) electron microscopy. To understand the photocatalytic and antibacterial behavior of the Pt-NPs/TiO2-NTs, simultaneous treatment of Escherichia coli and cyclohexane was conducted while varying the catalyst time decoration. We noticed a complete bacterial inactivation rate with 90% VOC removal within 60 min of visible light irradiation. Moreover, the Langmuir–Hinshelwood model correlated well with the experimental results of the photocatalytic treatment of indoor air.

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Comparison of Ga2O3 and TiO2 Nanostructures for Photocatalytic Degradation of Volatile Organic Compounds

Catalysts ◽

10.3390/catal10050545 ◽

2020 ◽

Vol 10 (5) ◽

pp. 545 ◽

Cited By ~ 2

Author(s):

Tae Hee Yoo ◽

Heejoong Ryou ◽

In Gyu Lee ◽

Junsang Cho ◽

Byung Jin Cho ◽

...

Keyword(s):

Photocatalytic Activity ◽

Volatile Organic Compounds ◽

Photocatalytic Degradation ◽

Organic Compounds ◽

Reaction Rate Constant ◽

X Ray Diffraction ◽

Volatile Organic ◽

Ultraviolet C ◽

Infrared Spectrometer ◽

Tio2 Nanostructures

The photocatalytic degradation of formaldehyde, acetaldehyde, toluene, and styrene are compared using monoclinic Ga2O3 and anatase TiO2 nanostructures under ultraviolet-C irradiation. These Ga2O3 and TiO2 photocatalysts are characterized using a field emission scanning electron microscope, a powder X-ray diffraction system, the Brunauer–Emmett–Teller method, and a Fourier transform infrared spectrometer. The Ga2O3 shows a higher reaction rate constant (k, min−1) than TiO2 by a factor of 7.1 for toluene, 8.1 for styrene, 3.1 for formaldehyde, and 2.0 for acetaldehyde. The results demonstrate that the photocatalytic activity ratio of the Ga2O3 over the TiO2 becomes more prominent toward the aromatic compounds compared with the nonaromatic compounds. Highly energetic photo-generated carriers on the conduction/valence band-edge of the Ga2O3, in comparison with that of the TiO2, result in superior photocatalytic activity, in particular on aromatic volatile organic compounds (VOCs) with a high bond dissociation energy.

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A Highly Efficient Volatile Organic Compounds Gas Sensor Based on Molybdenum Oxide Applied in Air Detection Inside Vehicles

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2021.3047 ◽

2021 ◽

Vol 16 (6) ◽

pp. 993-997

Author(s):

Jinying Zhou ◽

Yan Liu ◽

Lei Xu ◽

Jun Long

Keyword(s):

Volatile Organic Compounds ◽

Gas Sensor ◽

Organic Compounds ◽

Gas Sensing ◽

Structural Features ◽

X Ray Diffraction ◽

Sensing Material ◽

Highly Sensitive ◽

Volatile Organic ◽

Promising Application

Volatile organic compounds (VOCs) are the major air pollutants inside vehicles. In this research, a highly sensitive gas sensor was developed based on an excellent sensing material and explored for VOCs sensing application. The X-ray diffraction and scanning electron microscopy were performed to evaluate the detailed structural features of sensing material. From the gas-sensing property tests to the three representative VOCs vapors, containing xylene, toluene and formaldehyde, the gas sensor fabricated from the exceptional sensing material significantly responses to the three VOCs vapors. In particular, the xylene response of the sensor is slightly larger than the other two gas response. Thus, the fabricated sensor could be a promising application for VOCs detection inside vehicles.

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