Quaternary Holey Carbon Nanohorns/SnO2/ZnO/PVP Nano-Hybrid as Sensing Element for Resistive-Type Humidity Sensor

In this study, a resistive humidity sensor for moisture detection at room temperature is presented. The thin film proposed as a critical sensing element is based on a quaternary hybrid nanocomposite CNHox//SnO2/ZnO/PVP (oxidated carbon nanohorns–tin oxide–zinc oxide–polyvinylpyrrolidone) at the w/w/w/w ratios of 1.5/1/1/1 and 3/1/1/1. The sensing structure consists of a Si/SiO2 dielectric substrate and interdigitated transducers (IDT) electrodes, while the sensing film layer is deposited through the drop-casting method. Morphology and composition of the sensing layers were investigated through scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction, and Raman spectroscopy. Each quaternary hybrid nanocomposite-based thin film’s relative humidity (RH) sensing capability was analyzed by applying a direct current with known intensity between two electrodes and measuring the voltage difference when varying the RH from 0% to 100% in a humid nitrogen atmosphere. While the sensor with CNHox/SnO2/ZnO/PVP at 1.5/1/1/1 as the sensing layer has the better performance in terms of sensitivity, the structure employing CNHox//SnO2/ ZnO/PVP at 3/1/1/1 (mass ratio) as the sensing layer has a better performance in terms of linearity. The contribution of each component of the quaternary hybrid nanocomposites to the sensing performance is discussed in relation to their physical and chemical properties. Several alternative sensing mechanisms were taken into consideration and discussed. Based on the measured sensing results, we presume that the impact of the p-type semiconductor behavior of CNHox, in conjunction with the swelling of the hydrophilic polymer, is dominant and leads to the overall increasing resistance of the sensing film.

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MgO Refractory Doped with ZrO2 Nanoparticles: Influence of Cold Isostatic and Uniaxial Pressing and Sintering Temperature in the Physical and Chemical Properties

Metals ◽

10.3390/met9121297 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1297 ◽

Cited By ~ 1

Author(s):

Cristian Gómez-Rodríguez ◽

Daniel Fernández-González ◽

Linda Viviana García-Quiñonez ◽

Guadalupe Alan Castillo-Rodríguez ◽

Josué Amilcar Aguilar-Martínez ◽

...

Keyword(s):

Chemical Properties ◽

Cold Isostatic Pressing ◽

Zro2 Nanoparticles ◽

Furnace Lining ◽

Physical And Chemical Properties ◽

X Ray ◽

Isostatic Pressing ◽

Physical And Chemical ◽

The Impact ◽

And Chemical Properties

The chemical environment and the internal conditions of the furnaces and ladles are extremely aggressive for the refractories, so metallurgical industries demand refractory linings with greater durability and resistance to avoid unforeseen stoppages and to reduce the changes of the furnace lining. Therefore, the current work aims to evaluate the impact of the additions of ZrO2-nanoparticles (1, 3, and 5 wt. %) in magnesia-based bricks. A comparative study of the physical and chemical properties in bricks obtained using two cold pressing techniques (uniaxial and isostatic pressing) and two sintering temperatures (1550 and 1650 °C) was carried out. The microstructure and crystalline phase characteristics obtained after the heat treatments and the slag corrosion test was studied using scanning electron microscopy/electron dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). The results reveal that the sample with 5 wt. % of ZrO2 nanoparticles (obtained by cold isostatic pressing and sintering at 1650 °C) has the lowest porosity and greatest resistance to penetration of blast furnace slag.

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Arsenic Removal from Arsenopyrite-Bearing Iron Ore and Arsenic Recovery from Dust Ash by Roasting Method

Processes ◽

10.3390/pr7100754 ◽

2019 ◽

Vol 7 (10) ◽

pp. 754 ◽

Cited By ~ 3

Author(s):

Rijin Cheng ◽

Hua Zhang ◽

Hongwei Ni

Keyword(s):

Inductively Coupled Plasma ◽

Iron Ore ◽

Arsenic Removal ◽

Chemical Properties ◽

Atomic Emission ◽

Nitrogen Atmosphere ◽

Emission Spectrometry ◽

Plasma Atomic Emission Spectrometry ◽

X Ray ◽

Reducing Atmosphere

In most cases, arsenic is an unfavorable element in metallurgical processes. The mechanism of arsenic removal was investigated through roasting experiments performed on arsenopyrite-bearing iron ore. Thermodynamic calculation of arsenic recovery was carried out by FactSage 7.0 software (Thermfact/CRCT, Montreal, Canada; GTT-Technologies, Ahern, Germany). Moreover, the arsenic residues in dust ash were recovered by roasting dust ash in a reducing atmosphere. Furthermore, the corresponding chemical properties of the roasted ore and dust ash were determined by X-ray diffraction, inductively coupled plasma atomic emission spectrometry, and scanning electron microscopy, coupled with energy-dispersive X-ray spectroscopy. The experimental results revealed that the arsenic in arsenopyrite-bearing iron ore can be removed in the form of As2O3(g) in an air or nitrogen atmosphere by a roasting method. The efficiency of arsenic removal through roasting in air was found to be less than that in nitrogen atmosphere. The method of roasting in a reducing atmosphere is feasible for arsenic recovery from dust ash. When the carbon mass ratio in dust ash is 1.83%, the arsenic removal products is almost volatilized and recovered in the form of As2O3(g).

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Synthesis of titanium nitride via hybrid nanocomposites based on mesoporous TiO2/acrylonitrile

Scientific Reports ◽

10.1038/s41598-021-84484-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Claudiu Locovei ◽

Anita-Laura Chiriac ◽

Andreea Miron ◽

Sorina Iftimie ◽

Vlad-Andrei Antohe ◽

...

Keyword(s):

Titanium Nitride ◽

Hybrid Composites ◽

Nitrogen Atmosphere ◽

Sem Analysis ◽

Hybrid Nanocomposites ◽

Thermal Treatments ◽

Nitrogen Flow ◽

Hybrid Nanocomposite ◽

Xrd Patterns ◽

Different Content

AbstractIn the present study, the synthesis of titanium nitride (TiN) by carbothermal reduction nitridation (CRN) reaction using nanocomposites made of mesoporous TiO2/acrylonitrile with different content of inorganic phase were explored. The choice of hybrid nanocomposite as precursor for the synthesis of TiN was made due to the possibility of having an intimate interface between the organic and inorganic phases in the mixture that can favours CRN reaction. Subsequently, the hybrid composites have been subjected to four-step thermal treatments at 290 °C, 550 °C, 1000 °C and 1400 °C under nitrogen atmosphere. The XRD results after thermal treatment at 1000 °C under nitrogen flow show the coexistence of two crystalline phases of TiO2, i.e. anatase and rutile, as well as TiN phase, together with the detection of amorphous carbon that proved the initiation of CRN reaction. Furthermore, the observations based on XRD patterns of samples thermally treated at 1400 °C in nitrogen atmosphere were in agreement with SEM analysis, that shows the formation of TiN by CRN reaction via hybrid nanocomposites mesoporous TiO2/acrylonitrile.

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Polysulfone Membranes Based Hybrid Nanocomposites for the Adsorptive Removal of Hg(II) Ions

Polymers ◽

10.3390/polym13162792 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2792

Author(s):

Abeer M. Alosaimi

Keyword(s):

Carbon Nanotubes ◽

High Performance ◽

Carbon Nanomaterials ◽

Chemical Properties ◽

Inorganic Nanoparticles ◽

Hybrid Nanocomposites ◽

Inversion Method ◽

Hybrid Nanocomposite ◽

Nanocomposite Membranes ◽

Oxidized Carbon

Organic–inorganic nanoparticles, which can improve and modify the mechanical and chemical properties of polymers, have been used as fillers to prepare high-performance hybrid nanocomposite membranes. In this study, we explored whether the incorporation of organic nanofillers (graphene (G), graphene oxide (GO), carbon nanotubes (CNTs), or oxidized carbon nanotubes (CNTOxi)) into polysulfone (PSF) and montmorillonite (MMt)-modified PSF membranes could enhance membrane performance for the removal of heavy metal ions from contaminated solutions. These hybrid membranes were prepared by a phase inversion method using chloroform as the solvent. The surface morphologies of the membranes revealed good dispersibility of the organoclay and carbon nanomaterials in the PSF matrix. The hybrid nanocomposite membranes showed significantly improved thermal stability and mechanical properties as compared to the pristine PSF and PSF/MMt membranes. The adsorption efficiencies of these hybrid adsorptive membranes for Hg(II), Pb(II), Sr(II), Fe(III), Zn(II), Ni(II), Al(III), Co(II), Y(III), and Cr(III) were investigated. The PSF/MMt/CNTOxi and PSF/MMt/GO membranes exhibited the highest adsorption efficiencies. In particular, these adsorptive membranes showed selectivity toward Hg(II), and the Hg(II) extraction percentage was maximized at pH 2. The maximum Hg(II) adsorption capacities of PSF/MMt/CNTOxi and PSF/MMt/GO were 151.36 and 144.89 mg/g, respectively, and the adsorption isotherm was in approval with the Langmuir model. These hybrid nanocomposites can be used in water purification application.

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Effects of Formulated Nano-Urea Hydroxyapatite Slow Release Fertilizer Composite on the Physical, Chemical Properties, Growth and Yield of Cyamopsis tetragonoloba (Cluster Beans)

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.22975 ◽

2020 ◽

Vol 33 (1) ◽

pp. 159-165

Author(s):

Shylaja Singam ◽

Anand Rao Mesineni ◽

Ch. Shilpa Chakra

Keyword(s):

High Surface ◽

High Surface Area ◽

Chemical Properties ◽

Growth And Yield ◽

Precipitation Method ◽

Cyamopsis Tetragonoloba ◽

X Ray ◽

Bean Plants ◽

Co Precipitation ◽

The Impact

Urea and phosphorous fertilizers are commonly used in agriculture but, due to their solubility in water and transportation, cause eutrophication. Hence, it is thought worthwhile to investigate for urea hydroxyapatite nanoparticles which have less mobility and could supply required N and P macronutrients to the crops. These high surface area nanoparticles are synthesized through chemical co-precipitation method and it is assumed that due to their biocompatibility, act as rich phosphorous and nitrogen source. These are characterized by powder X-ray diffraction (PXRD), dynamic light scattering (DLS), scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX) and Fourier transform infrared (FT-IR). The impact of urea hydroxyapatite nanofertilizer on growth and yield of cluster bean plants for the period of four months has been carried out. The experimental results have shown that the usage of these nanofertilizers have enhanced both the plant growth and yield. The application of urea hydroxyapatite nanocomposites for the bio-availability of plants considered to be environment friendly.

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Changes of electronic properties of AlGaN/GaN HEMTs by surface treatment

MRS Proceedings ◽

10.1557/opl.2014.937 ◽

2014 ◽

Vol 1736 ◽

Author(s):

W. Pletschen ◽

St. Linkohr ◽

L. Kirste ◽

V. Cimalla ◽

S. Müller ◽

...

Keyword(s):

Electronic Properties ◽

Electronic Transport ◽

Layer Structure ◽

Nitrogen Atmosphere ◽

Surface Barrier ◽

X Ray ◽

Device Processing ◽

Layer Structures ◽

Hall Effect Measurements ◽

The Impact

ABSTRACTThe impact of device processing and plasma treatments at different plasma conditions on the electronic transport properties of GaN/AlGaN/GaN heterostructures was investigated as well as annealing in nitrogen atmosphere at 425°C. The electrical properties are characterized by Hall-effect measurements while electron spectroscopy and X-ray measurements are used to investigate changes in the surface chemical composition and in the layer structure, respectively. It is demonstrated that these layer structures are quite sensitive even to non-plasma based processing. Furthermore, treatments in SF6 and N2 based plasmas strongly affect the 2DEG properties of the heterostructure due to altering of the surface barrier accompanied by thinning of the layer structure. Depending on the layer structure and the plasma conditions used the electronic properties may be recovered by annealing.

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Ternary Oxidized Carbon Nanohorns/TiO2/PVP Nanohybrid as Sensitive Layer for Chemoresistive Humidity Sensor

Chemistry Proceedings ◽

10.3390/csac2021-10616 ◽

2021 ◽

Vol 5 (1) ◽

pp. 12

Author(s):

Bogdan-Catalin Serban ◽

Octavian Buiu ◽

Marius Bumbac ◽

Roxana Marinescu ◽

Niculae Dumbravescu ◽

...

Keyword(s):

Thin Film ◽

Relative Humidity ◽

Nitrogen Atmosphere ◽

Sensing Element ◽

Sensitive Layer ◽

Sio2 Substrate ◽

Casting Technique ◽

Carbon Nanohorns ◽

Comb Structure ◽

Oxidized Carbon

The relative humidity (RH) sensing response of a chemoresistive sensor using a novel ternary hybrid nanocomposite film as a sensing element is presented. The sensitive layer was obtained by employing the drop-casting technique for depositing a thin film of nanocomposite between the electrodes of an interdigitated (IDT) structure. The sensing support structure consists of an IDT dual-comb structure fabricated on a oSi-SiO2 substrate. The IDT comprises chromium, as an adhesion layer (10 nm thickness), and a gold layer (100 nm thickness). The sensing capability of a novel thin film based on a ternary hybrid made of oxidated carbon nanohorns–titanium dioxide–polyvinylpyrrolidone (CNHox/TiO2/PVP) nanocomposite was investigated by applying a direct current with known intensity between the two electrodes of the sensing structure, and measuring the resulting voltage difference, while varying the RH from 0% to 100% in a humid nitrogen atmosphere. The ternary hybrid-based thin film’s resistance increased when the sensors were exposed to relative humidity ranging from 0 to 100%. It was found that the performance of the new chemoresistive sensor is consistent with that of the capacitive commercial sensor used as a benchmark. Raman spectroscopy was used to provide information on the composition of the sensing layer and on potential interactions between constituents. Several sensing mechanisms were considered and discussed, based on the interaction of water molecules with each component of the ternary nanohybrid. The sensing results obtained lead to the conclusion that the synergic effect of the p-type semiconductor behavior of the CNHox and the PVP swelling process plays a pivotal role in the overall resistance decrease of the sensitive film.

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Blending Ratio Effect of ZnPc/ZnO Hybrid Nanocomposite on Surface Morphology and Structural Properties

Journal of Physics Conference Series ◽

10.1088/1742-6596/2114/1/012015 ◽

2021 ◽

Vol 2114 (1) ◽

pp. 012015

Author(s):

K. F. Abbas ◽

A. F. Abdulameer

Keyword(s):

Hybrid Nanocomposites ◽

Zinc Phthalocyanine ◽

Morphological Properties ◽

Hybrid Nanocomposite ◽

Spherical Nanoparticles ◽

X Ray Diffraction ◽

Homogeneous Surface ◽

X Ray ◽

Glass Substrates ◽

Pure Compounds

Abstract Recently, organic/inorganic hybrid nanocomposites being the future in electronic applications. In this paper, we have investigated hybrid nanocomposite zinc phthalocyanine (ZnPc)/zinc oxide nanoparticles (ZnO). ZnPc/ZnO hybrid nanocomposites were prepared with different ratios (wt/wt) (1/0), (0/1), (0.75/0.25), (0.5/0.5), (0.25/0.75), and, deposited on glass substrates by spin coating technique. X-Ray diffraction investigate the structural of ZnPc/ZnO thin films and studied the morphological properties using field emission scan electron microscopy, the surface of ZnPc/ZnO hybrid nanocomposites shows the presence of nanorod-like structures represented the organic material (ZnPc) and spherical nanoparticles for (ZnO), that is depending on the ratio of the blend. In ratio (0.5/0.5) we get the preferred homogeneous surface between like-nanorod and spherical shapes were show various properties from pure compounds which used to prepare the blend. The distribution of ZnO nanoparticles on ZnPc particles nanorods led to the disappearance feature of ZnO morphological characterize and ZnPc decorated was dominated on the hybrid nanocomposite structure.

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Terbium-Based AGuIX-Design Nanoparticle to Mediate X-ray-Induced Photodynamic Therapy

Pharmaceuticals ◽

10.3390/ph14050396 ◽

2021 ◽

Vol 14 (5) ◽

pp. 396

Author(s):

Joël Daouk ◽

Mathilde Iltis ◽

Batoul Dhaini ◽

Denise Béchet ◽

Philippe Arnoux ◽

...

Keyword(s):

Photodynamic Therapy ◽

Energy Transfer ◽

Radiation Treatment ◽

Chemical Properties ◽

Similar Rate ◽

X Rays ◽

X Ray ◽

Physico Chemical ◽

Species Production ◽

The Impact

X-ray-induced photodynamic therapy is based on the energy transfer from a nanoscintillator to a photosensitizer molecule, whose activation leads to singlet oxygen and radical species generation, triggering cancer cells to cell death. Herein, we synthesized ultra-small nanoparticle chelated with Terbium (Tb) as a nanoscintillator and 5-(4-carboxyphenyl succinimide ester)-10,15,20-triphenyl porphyrin (P1) as a photosensitizer (AGuIX@Tb-P1). The synthesis was based on the AGuIX@ platform design. AGuIX@Tb-P1 was characterised for its photo-physical and physico-chemical properties. The effect of the nanoparticles was studied using human glioblastoma U-251 MG cells and was compared to treatment with AGuIX@ nanoparticles doped with Gadolinium (Gd) and P1 (AguIX@Gd-P1). We demonstrated that the AGuIX@Tb-P1 design was consistent with X-ray photon energy transfer from Terbium to P1. Both nanoparticles had similar dark cytotoxicity and they were absorbed in a similar rate within the cells. Pre-treated cells exposure to X-rays was related to reactive species production. Using clonogenic assays, establishment of survival curves allowed discrimination of the impact of radiation treatment from X-ray-induced photodynamic effect. We showed that cell growth arrest was increased (35%-increase) when cells were treated with AGuIX@Tb-P1 compared to the nanoparticle doped with Gd.

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Cu Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity and High Temperature Anatase Stability

10.26434/chemrxiv.7159733.v1 ◽

2018 ◽

Cited By ~ 2

Author(s):

Snehamol Mathew ◽

Priyanka Ganguly ◽

Stephen Rhatigan ◽

Vignesh Kumaravel ◽

Ciara Byrne ◽

...

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Density Functional ◽

Anatase Phase ◽

Sol Gel ◽

Chemical Properties ◽

Light Irradiation ◽

Health Concern ◽

Bacterial Inactivation ◽

X Ray

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO2) can effectively curb this growing threat. Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO2 (Cu-TiO2) was evaluated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO2 was carried out via sol-gel technique. Cu-TiO2 further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO2 anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO2 was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO2 was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu+ and Cu2+ ions by replacing Ti4+ ions in the TiO2 lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO2.

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