scholarly journals Rhombohedral Boron Nitride Epitaxy on ZrB2

2020 ◽  
Author(s):  
Laurent Souqui ◽  
Justinas Palisaitis ◽  
Naureen Ghafoor ◽  
Henrik Pedersen ◽  
Hans Högberg
Keyword(s):  
Electron Microscopy ◽  
Boron Nitride ◽  
Photoelectron Spectroscopy ◽  
Amorphous Material ◽  
Limited Area ◽  
Sem Images ◽  
Plan View ◽  
Minute Amount ◽  
X Ray ◽  
Rhombohedral Boron

<div>Epitaxial rhombohedral boron nitride films were deposited on ZrB<sub>2</sub>(0001)/4H-SiC(0001) by chemical vapor deposition at 1485 °C from the reaction of triethylboron and ammonia and with a minute amount of silane (SiH<sub>4</sub>). X-ray diffraction (XRD) φ-scans yield the epitaxial relationships of 𝑟−𝐵𝑁(0001)∥𝑍𝑟𝐵2(0001) out-of-plane and 𝑟−𝐵𝑁(1120)∥𝑍𝑟𝐵2(1120) in-plane. Cross-section transmission electron microscopy (TEM) micrographs showed that epitaxial break down of r-BN film occurs approximatively after 10 nm, above which epitaxial growth proceeds only in limited area up to 80 nm of film thickness. Both XRD and TEM demonstrate the formation of carbon- and nitrogen-containing cubic inclusions at the ZrB<sub>2</sub> surface. Quantitative analysis from X-ray photoelectron spectroscopy of the r-BN films shows B/N ratios between 1.30 to 1.20 and an O content of 3 to 4 at.%. Plan-view scanning electron microscopy (SEM) images reveal a surface morphology where an amorphous material comprising B, C, and N is surrounding the epitaxial twinned r-BN crystals. SiH<sub>4</sub> exposure prior to growth was found to reduce the amount of the amorphous phase on the surface. Defects such as pitting were also observed on the ZrB<sub>2</sub> template surface.</div><div><br></div>

scholarly journals Rhombohedral Boron Nitride Epitaxy on ZrB2

2020 ◽  
Author(s):  
Laurent Souqui ◽  
Justinas Palisaitis ◽  
Naureen Ghafoor ◽  
Henrik Pedersen ◽  
Hans Högberg
Keyword(s):  
Electron Microscopy ◽  
Boron Nitride ◽  
Photoelectron Spectroscopy ◽  
Amorphous Material ◽  
Limited Area ◽  
Sem Images ◽  
Plan View ◽  
Minute Amount ◽  
X Ray ◽  
Rhombohedral Boron

<div>Epitaxial rhombohedral boron nitride films were deposited on ZrB<sub>2</sub>(0001)/4H-SiC(0001) by chemical vapor deposition at 1485 °C from the reaction of triethylboron and ammonia and with a minute amount of silane (SiH<sub>4</sub>). X-ray diffraction (XRD) φ-scans yield the epitaxial relationships of 𝑟−𝐵𝑁(0001)∥𝑍𝑟𝐵2(0001) out-of-plane and 𝑟−𝐵𝑁(1120)∥𝑍𝑟𝐵2(1120) in-plane. Cross-section transmission electron microscopy (TEM) micrographs showed that epitaxial break down of r-BN film occurs approximatively after 10 nm, above which epitaxial growth proceeds only in limited area up to 80 nm of film thickness. Both XRD and TEM demonstrate the formation of carbon- and nitrogen-containing cubic inclusions at the ZrB<sub>2</sub> surface. Quantitative analysis from X-ray photoelectron spectroscopy of the r-BN films shows B/N ratios between 1.30 to 1.20 and an O content of 3 to 4 at.%. Plan-view scanning electron microscopy (SEM) images reveal a surface morphology where an amorphous material comprising B, C, and N is surrounding the epitaxial twinned r-BN crystals. SiH<sub>4</sub> exposure prior to growth was found to reduce the amount of the amorphous phase on the surface. Defects such as pitting were also observed on the ZrB<sub>2</sub> template surface.</div><div><br></div>

Synthesis of TiO2 and ZrO2 nanomaterials for the degradation of nerve agent simulants

2021 ◽  
Vol 11 (1) ◽  
pp. 105-110
Author(s):  
Dung Le Van ◽  
Phuong Dang Tuyet ◽  
Trinh Nguyen Duy ◽  
Manh Nguyen Ba
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Warfare Agent ◽  
Catalytic Performance ◽  
Sem Images ◽  
X Ray ◽  
Nitrophenyl Phosphate ◽  
Tio2 Nanomaterials ◽  
Adsorption Desorption

TiO2 and ZrO2 nanomaterials were successfully synthesized by sol gel method. Samples were characterized by X-ray difraction (XRD), Fourier-transform infrared spectroscopy (FTIR), N2 adsorption–desorption, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS),  SEM images and TEM images of TiO2 and ZrO2 samples showed the particle size of 10–20 nm. The results have revealed highly porous structure of ZrO2 and TiO2 nanomaterials with specific surface area of 116 m2g-1 and 125 m2g-1, respectively. The TiO2 and ZrO2 materials were used as the degradation of dimethyl 4-nitrophenyl phosphate (DMNP) chemical warfare agent emulator. The ZrO2 nanomaterial exhibited highly catalytic performance of DMNP degradation and the conversion reached to the value of 90.64 %, after 120 min of reaction.

Fabrication and Characterization of Poly(vinyl Alcohol)/Functionalized Graphene Oxide Nanofibers Produced by Electrospinning Method

2013 ◽  
Vol 747 ◽  
pp. 405-408
Author(s):  
Yuan Hsiang Yu ◽  
Chih Jie Jan
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Functionalized Graphene ◽  
Sem Images ◽  
Functionalized Graphene Oxide ◽  
X Ray ◽  
Electrospinning Method

A series of poly (vinyl alcohol) (PVA)/functionalized graphene oxide (FGO) nanofibers with low feeding ratios of FGO to PVA were fabricated by electrospinning method. In this study, the prepared PVA/FGO nanocomposites were dispersed in water phase followed by electrospinning treatment under different operational parameters (i.e., applied voltage, feeding rate and FGO contents) to give nanofibers of various diameters and morphologies. The morphology, diameter and structure of electrospun nanofibers and FGO were investigated by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), (TGA) and differential scanning calorimetry (DSC). SEM images showed that the morphologies of the nanofibers were improved by the incorporation of FGO at a low loading content (e.g., 0.1~0.5 wt %) as compared to pure electrospun PVA. The crystallinity and thermal stability of PVA/FGO nanofibers were also studied.

The Effect of the Microstructure of Diffusion Barriers on the Palladium Activation for Electroless Copper Deposition

2002 ◽  
Vol 716 ◽  
Author(s):  
Seok Woo Hong ◽  
Yong Sun Lee ◽  
Ki-Chul Park ◽  
Jong-Wan Park
Keyword(s):  
Electron Microscopy ◽  
Diffusion Barriers ◽  
Copper Deposition ◽  
X Ray Diffraction ◽  
Plan View ◽  
X Ray ◽  
Transmission Electron ◽  
Electroless Copper ◽  
Sheet Resistance Measurement ◽  
Scanning Electron

AbstractThe effect of microstructure of dc magnetron sputtered TiN and TaN diffusion barriers on the palladium activation for autocatalytic electroless copper deposition has been investigated by using X-ray diffraction, sheet resistance measurement, field emission scanning electron microscopy (FE-SEM) and plan view transmission electron microscopy (TEM). The density of palladium nuclei on TaN diffusion barrier increases as the grain size of TaN films decreases, which was caused by increasing nitrogen content in TaN films. Plan view TEM results of TiN and TaN diffusiton barriers showed that palladium nuclei formed mainly on the grain boundaries of the diffusion barriers.

Antibacterial silver-diatomite nanocomposite ceramic with low silver release

2019 ◽  
Vol 20 (2) ◽  
pp. 633-643
Author(s):  
Xiaopeng Qi ◽  
Junwei Chen ◽  
Qian Li ◽  
Hui Yang ◽  
Honghui Jiang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Water Treatment ◽  
Photoelectron Spectroscopy ◽  
Bactericidal Effect ◽  
Ceramic Filter ◽  
Ceramic Filters ◽  
X Ray ◽  
E Coli ◽  
Point Of Use ◽  
Silver Release

Abstract There is an urgent need for an effective and long-lasting ceramic filter for point-of-use water treatment. In this study, silver-diatomite nanocomposite ceramic filters were developed by an easy and effective method. The ceramic filters have a three-dimensional interconnected pore structure and porosity of 50.85%. Characterizations of the silver-diatomite nanocomposite ceramic filters were performed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Silver nanoparticles were confirmed to be formed in situ in the ceramic filter. The highest silver concentration in water was 0.24 μg/L and 2.1 μg/L in short- and long-term experiments, indicating very low silver-release properties of silver-diatomite nanocomposite ceramic filter. The nanocomposite ceramics show strong bactericidal activity. When contact time with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) of 105 colony forming units (CFU)/mL exceeded 3 h, the bactericidal rates of the four different silver content ceramics against E. coli and S. aureus were all 100%. Strong bactericidal effect against E. coli with initial concentration of 109 CFU/mL were also observed in ceramic newly obtained and ceramic immersed in water for 270 days, demonstrating its high stability. The silver-diatomite nanocomposite ceramic filters could be a promising candidate for point-of-use water treatment.

scholarly journals Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 124
Author(s):  
Srihasam Saiganesh ◽  
Thyagarajan Krishnan ◽  
Golla Narasimha ◽  
Hesham S. Almoallim ◽  
Sulaiman Ali Alhari ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Optical Properties ◽  
Rare Earth ◽  
Nickel Oxide ◽  
Photoelectron Spectroscopy ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Nio Nanoparticles ◽  
X Ray ◽  
Sesbania Grandiflora

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

scholarly journals Thermoelectric Generator Using Polyaniline-Coated Sb2Se3/β-Cu2Se Flexible Thermoelectric Films

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1518
Author(s):  
Minsu Kim ◽  
Dabin Park ◽  
Jooheon Kim
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Field Emission ◽  
Photoelectron Spectroscopy ◽  
Thermoelectric Generator ◽  
Hydrothermal Reaction ◽  
Water Evaporation ◽  
Pani Film ◽  
Portable Devices ◽  
X Ray

Herein, Sb2Se3 and β-Cu2Se nanowires are synthesized via hydrothermal reaction and water evaporation-induced self-assembly methods, respectively. The successful syntheses and morphologies of the Sb2Se3 and β-Cu2Se nanowires are confirmed via X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), and field emission transmission electron microscopy (FE-TEM). Sb2Se3 materials have low electrical conductivity which limits application to the thermoelectric generator. To improve the electrical conductivity of the Sb2Se3 and β-Cu2Se nanowires, polyaniline (PANI) is coated onto the surface and confirmed via Fourier-transform infrared spectroscopy (FT-IR), FE-TEM, and XPS analysis. After coating PANI, the electrical conductivities of Sb2Se3/β-Cu2Se/PANI composites were increased. The thermoelectric performance of the flexible Sb2Se3/β-Cu2Se/PANI films is then measured, and the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is shown to provide the highest power factor of 181.61 μW/m·K2 at 473 K. In addition, a thermoelectric generator consisting of five legs of the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is constructed and shown to provide an open-circuit voltage of 7.9 mV and an output power of 80.1 nW at ΔT = 30 K. This study demonstrates that the combination of inorganic thermoelectric materials and flexible polymers can generate power in wearable or portable devices.

scholarly journals Efficient Adsorption of Methylene Blue by Porous Biochar Derived from Soybean Dreg Using a One-Pot Synthesis Method

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 661
Author(s):  
Zhiwei Ying ◽  
Xinwei Chen ◽  
He Li ◽  
Xinqi Liu ◽  
Chi Zhang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Synthesis Method ◽  
Urban Pollution ◽  
Maximum Adsorption Capacity ◽  
One Pot ◽  
Average Pore ◽  
X Ray ◽  
Isotherm Equation

Soybean dreg is a by-product of soybean products production, with a large consumption in China. Low utilization value leads to random discarding, which is one of the important sources of urban pollution. In this work, porous biochar was synthesized using a one-pot method and potassium bicarbonate (KHCO3) with low-cost soybean dreg (SD) powder as the carbon precursor to investigating the adsorption of methylene blue (MB). The prepared samples were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental analyzer (EA), Brunauer-Emmett-Teller (BET), X-ray diffractometer (XRD), Raman spectroscopy (Raman), Fourier transform infrared spectrometer (FTIR), and X-ray photoelectron spectroscopy (XPS). The obtained SDB-K-3 showed a high specific surface area of 1620 m2 g−1, a large pore volume of 0.7509 cm3 g−1, and an average pore diameter of 1.859 nm. The results indicated that the maximum adsorption capacity of SDB-K-3 to MB could reach 1273.51 mg g−1 at 318 K. The kinetic data were most consistent with the pseudo-second-order model and the adsorption behavior was more suitable for the Langmuir isotherm equation. This study demonstrated that the porous biochar adsorbent can be prepared from soybean dreg by high value utilization, and it could hold significant potential for dye wastewater treatment in the future.

scholarly journals Investigation of Spin Coating Cerium-Doped Hydroxyapatite Thin Films with Antifungal Properties

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 464
Author(s):  
Simona Liliana Iconaru ◽  
Mihai Valentin Predoi ◽  
Patrick Chapon ◽  
Sofia Gaiaschi ◽  
Krzysztof Rokosz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Spin Coating ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
X Ray ◽  
Antifungal Properties ◽  
Scanning Electron

In this study, the cerium-doped hydroxyapatite (Ca10−xCex(PO4)6(OH)2 with xCe = 0.1, 10Ce-HAp) coatings obtained by the spin coating method were presented for the first time. The stability of the 10Ce-HAp suspension particles used in the preparation of coatings was evaluated by ultrasonic studies, transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The surface morphology of the 10Ce-HAp coating was studied by SEM and atomic force microscopy (AFM) techniques. The obtained 10Ce-HAp coatings were uniform and without cracks or unevenness. Glow discharge optical emission spectroscopy (GDOES) and X-ray photoelectron spectroscopy (XPS) were used for the investigation of fine chemical depth profiling. The antifungal properties of the HAp and 10Ce-HAp suspensions and coatings were assessed using Candida albicans ATCC 10231 (C. albicans) fungal strain. The quantitative antifungal assays demonstrated that both 10Ce-HAp suspensions and coatings exhibited strong antifungal properties and that they successfully inhibited the development and adherence of C. albicans fungal cells for all the tested time intervals. The scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) visualization of the C. albicans fungal cells adherence to the 10Ce-HAp surface also demonstrated their strong inhibitory effects. In addition, the qualitative assays also suggested that the 10Ce-HAp coatings successfully stopped the biofilm formation.

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