Nonthermal Plasma-Assisted Synthesis of Molybdenum Carbide Thin Film Catalysts

2007 ◽  
Vol 1 (1) ◽  
Author(s):  
G. Campbell ◽  
K. Nelson ◽  
C. L. Heitzman ◽  
K. Brezinsky ◽  
A. Saveliev
Keyword(s):  
Photoelectron Spectroscopy ◽  
Molybdenum Carbide ◽  
Nonthermal Plasma ◽  
Ethylene Concentration ◽  
Transmission Electron ◽  
Thin Film Catalysts ◽  
Catalyst Production ◽  
Novel Method ◽  
Water Gas

Optimization of the nonthermal plasma-assisted method of synthesizing molybdenum carbide thin films on molybdenum particle substrates was initiated using a previously existing experimental setup. The yield of the apparatus used has increased by 20% as the result of redesign. The molybdenum carbide produced through nonthermal plasma has been characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It is tentatively observed by using the TEM that an ethylene concentration of 3% gives the best molybdenum carbide surface layer. The quality of the product is unclear, indicating that further characterization is necessary. This novel method of catalyst production has been tested in very preliminary experiments with a water-gas shift reactor and the CO2 conversion was 0.5%, suggesting, again, that further optimization is necessary.

Plasma Assisted Synthesis of a Molybdenum Carbide Catalyst

2008 ◽  
Vol 2 (1) ◽  
Author(s):  
C. Lopez ◽  
D. Meyers ◽  
A. Saddawi ◽  
A. Saveliev ◽  
K. Brezinsky
Keyword(s):  
Molybdenum Carbide ◽  
Water Gas Shift ◽  
Synthesis Product ◽  
Water Gas Shift Reaction ◽  
Molybdenum Metal ◽  
Transmission Electron ◽  
Novel Method ◽  
Non Thermal Plasma ◽  
Shift Reaction ◽  
Water Gas

A novel method for the production of a nano-structured molybdenum carbide catalyst using non-thermal plasma is described. This synthesis involves the carburization of a molybdenum metal powder precursor using ethylene as the carbon source. Transmission electron microscopy (TEM) showed the presence of a Mo2C-β crystal structure and a 9�2 nm layer of what was suspected to be Mo2C absent in the molybdenum precursor. Catalytic testing in the water gas shift reaction (WGS) showed no difference in activity between the unreduced synthesis product and the control run.

SYNTHESIS OF ZnS:Mn/SILICA CORE/SHELL MICROSPHERES WITH A COMBINATION OF SOL–GEL AND SELF-TEMPLATING TECHNIQUES

NANO ◽  
2014 ◽  
Vol 09 (03) ◽  
pp. 1450028
Author(s):  
QING ZHANG
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Fluorescence Emission ◽  
Core Shell ◽  
Reaction Conditions ◽  
Whole Process ◽  
Transmission Electron ◽  
Novel Method ◽  
Nanosilica Particles

Core/shell microspheres with functional Mn -doped ZnS microspheres ( ZnS : Mn ) as core and with nanosilica particles as shell were prepared by a combination of sol–gel and self-templating techniques. The characteristic of this novel method was that the whole process required neither additional surfactant nor stabilizer, which exempted from removing the template and reduced reaction steps compared to the conventional process. The morphologies, structure and particle size distribution of the resulting ZnS : Mn / SiO 2 microspheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. Surface chemical composition and optical properties were determined with X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectroscopy, respectively. In addition, the effects of reaction conditions on the structure and morphologies were investigated. Experimental results indicated that the resulting ZnS : Mn / SiO 2 microspheres were perfectly spherical with distinct core/shell structures, and exhibited stronger fluorescence emission.

scholarly journals Facile Synthesis and Characterization of Au Nanoclusters-Silica Fluorescent Composite Nanospheres

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Huiping Wang ◽  
Chaoyong Xu ◽  
Chengzhi Zheng ◽  
Wei Xu ◽  
Tianjiao Dong ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Acetate Buffer Solution ◽  
Fluorescent Properties ◽  
Buffer Solution ◽  
Au Nanoclusters ◽  
Water Dispersible ◽  
Transmission Electron ◽  
Microscope Imaging ◽  
Novel Method

We developed a novel method for the synthesis of Au nanoclusters (NCs) silica fluorescent composite nanospheres by mixing the as-prepared bovine serum albumin (BSA) protected Au NCs with amino-modified silica spheres in acetate buffer solution. The products were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), fluorescent microscope imaging (FLMI), and dynamic light scattering (DLS) measurements. The proposed method was simple, efficient, and inexpensive. In addition, the composite nanospheres exhibited favorable water-dispersible, stable, and fluorescent properties, potentially leading to further applications in chemical and biological sensors. A reasonable mechanism was also proposed for the formation of composite nanospheres.

Synthesis, Structure, and Electrochemical Properties of Li4Ti5O12

2006 ◽  
Vol 973 ◽  
Author(s):  
Chintalapalle V Ramana ◽  
Satoshi Utsunomiya ◽  
Rodney C Ewing ◽  
Udo Becker ◽  
Karim Zaghib ◽  
...  
Keyword(s):  
High Resolution ◽  
Photoelectron Spectroscopy ◽  
Electrode Materials ◽  
Negative Electrode ◽  
X Ray ◽  
Transmission Electron ◽  
Crystallographic Defects ◽  
Microscopy Techniques ◽  
Negative Electrode Materials

ABSTRACTLithium titanium oxide (Li4Ti5O12) spinels are promising negative electrode materials for application in energy technology. In this work, we have synthesized Li4Ti5O12 and investigated its structure, electronic properties, and electrochemical features using several analytical spectroscopy and microscopy techniques. The equally spaced lattice fringes obtained using by the high-resolution transmission electron microscopy (HRTEM) along with electron diffraction reveal that the grown Li4Ti5O12 is well crystallized in the spinel structure without any indication of crystallographic defects such as dislocations or misfits. The electronic structure determination using high-resolution X-ray photoelectron spectroscopy (XPS) coupled with compositional studies using energy dispersive X-ray spectrometry (EDS) indicate excellent chemical quality of the Li4Ti5O12. Under the optimal synthetic condition, the sample delivers a discharge capacity of 161 mAh/g at C/12. The good cyclability of Li4Ti5O12 is attributed to the small expansion (δV≈1%) of the elementary unit-cell.

GROWTH OF HIGHLY (0002) ORIENTED InN FILMS ON AlInN/AlN BILAYER

2013 ◽  
Vol 20 (02) ◽  
pp. 1350015 ◽  
Author(s):  
C. J. DONG ◽  
M. XU ◽  
W. LU ◽  
Q. Z. HUANG
Keyword(s):  
Photoelectron Spectroscopy ◽  
Rf Magnetron Sputtering ◽  
Interface Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hexagonal Wurtzite Crystal Structure ◽  
Transmission Electron ◽  
Aln Buffer ◽  
Microelectronic Materials

InN film with an AlInN/AlN bilayer buffer was deposited on Si(111) substrate by radio frequency (RF) magnetron sputtering. X-ray diffraction and Raman spectroscopy measurements reveal that the InN film is of hexagonal wurtzite crystal structure with highly (0002) preferred orientation. An Al0.24In0.76N interface layer of about ~50 nm was confirmed by transmission electron microscopy (TEM) and further analyzed by X-ray photoelectron spectroscopy (XPS). The quality of this film is remarkably better than InN films grown directly on Si substrate or with only an AlN buffer, due to the effective accommodation of mismatch between the film and substrate. Our results will be very useful in the fabrication of applicable nitride microelectronic materials.

scholarly journals Study on Hydrogenation Performance of Oil-Soluble Molybdenum Catalyst in Coal-Oil Co-Processing

2022 ◽  
Author(s):  
Guangyao Wang ◽  
Xiqian Wang ◽  
Yuan Zhao
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Heavy Fraction ◽  
X Ray Diffraction ◽  
Molybdenum Catalyst ◽  
X Ray ◽  
Transmission Electron ◽  
Novel Method ◽  
Scanning Electron

Abstract An oil-soluble molybdenum catalyst was synthesized by a simple and novel method and studied for hydrogenation in coal-oil co-processing. The catalyst was characterized by infrared spectrum (IR), thermogravimetry (TG), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The morphology and crystal structure of catalyst was characterized with scanning electron microscope (SEM) and high resolution transmission electron microscopy (HRTEM). The catalyst can be considered as a precursor that can be converted into active MoS2 components through thermal decomposition and sulfidation. The hydrogenation experiment was carried out by the model reactants of tetradecane and 2-methylnaphthalene with a change of reaction (405℃-445℃) temperature and concentrations of molybdenum catalyst (Mo conc. 0.6-10 mg/g), and results showed that the delightly hydrogenation function of catalyst is to improve the saturation of aromatic ring. The most abundant stacking numbers of decomposed catalyst were 2 and 3, accounting for 53% of all catalyst microcrystalline units. The rapid hydrogenation stage and the significant decrease of feed heavy fraction in co-processing experiment provided the evidence that the hydrogenation performance of the synthesized catalyst is remarkable in coal-oil co-processing.

Electronic and Atomic Properties of a-C:H/Semiconductor Interfaces

1989 ◽  
Vol 159 ◽  
Author(s):  
M. Wittmer ◽  
D. Ugolini ◽  
P. Oelhafen
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Semiconductor Materials ◽  
Interfacial Layers ◽  
Ion Channeling ◽  
Atomic Properties ◽  
Semiconductor Interfaces ◽  
Transmission Electron ◽  
Amorphous Hydrogenated Carbon

ABSTRACTWe have investigated the electronic and atomic properties of the interface between amorphous hydrogenated carbon (a-C:H) films and the semiconductor materials Si, Ge and GaAs with photoelectron spectroscopy, high resolution transmission electron microscopy and ion channeling technique. The different properties of the interfacial layers are summarized and compared to the adhesion quality of a-C:H films on these semiconductor materials.

Novel Method to Synthesize Ceria Coated Silica particles

2009 ◽  
Vol 1157 ◽  
Author(s):  
Myoung-hwan Oh ◽  
Jae Seok Lee ◽  
Sushant Gupta ◽  
Tae Kon Kim ◽  
Aniroddh Kaanna ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Silica Particles ◽  
X Ray Diffraction ◽  
Post Heat Treatment ◽  
X Ray ◽  
Transmission Electron ◽  
New Type ◽  
Novel Method ◽  
Alkoxide Method

AbstractMonodispersed ceria coated silica particles were prepared by a new type of ceria precursor. The ceria precursor was synthesized by alkoxide method, which employs ethanol as solvent. The synthesized particles were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was found that well-crystalline ceria coatings were deposited on the surface of the silica particles without post-heat treatment. In addition, the coated particles prepared by a new precursor were uniformly dispersed without the formation of hard aggregate as compared to those obtained by conventional method.

scholarly journals Preparation of uniformly dispersed N-isopropylacryl-amide/acrylic acid/nanosilver composite hydrogel and its anti-mold properties

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 441-454
Author(s):  
Rui Peng ◽  
Huilong Yu ◽  
Chungui Du ◽  
Jingjing Zhang ◽  
Ailian Hu ◽  
...  
Keyword(s):  
Particle Size ◽  
Acrylic Acid ◽  
Photoelectron Spectroscopy ◽  
Composite Hydrogel ◽  
The Novel ◽  
X Ray ◽  
Composite Hydrogels ◽  
Transmission Electron ◽  
Novel Method ◽  
Polymerization Method

To overcome the agglomeration tendency of nanosilver composite hydrogels and to improve their anti-mold properties, a method of preparing N-isopropylacrylamide/acrylic acid/nanosilver composite hydrogel was developed using the free radical polymerization method. The composite hydrogel was characterized via infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and X-ray photoelectron spectroscopy in order to explore the effects of the acrylic acid content on particle size and dispersion properties of the composite hydrogels. The elemental composition, microstructure, and anti-mold properties of the bamboo strips treated with the composite hydrogel were also determined. The results showed that the composite hydrogel prepared using the novel method described in this study had good dispersity. Composite hydrogels with the smallest particle size and optimized dispersion were produced when AAc concentration was 0.64 µL/mL. The composite hydrogel effectively filled and covered the bamboo cells after treatment. Moreover, it displayed good anti-mold properties as well as retaining the color of the bamboo.

A Novel Method to Improve the Dispersibility of Silicon Nitride Powders in Aqueous Media

NANO ◽  
2019 ◽  
Vol 14 (09) ◽  
pp. 1950118
Author(s):  
Bingjie Xu ◽  
Mengxing Li ◽  
Qi Chen ◽  
Pengfei Liu ◽  
Baosong Xu ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Photoelectron Spectroscopy ◽  
Aqueous Media ◽  
Colloidal Dispersion ◽  
Nitrogen Atmosphere ◽  
Initial Mass ◽  
Core Shell ◽  
Composite Powders ◽  
Transmission Electron ◽  
Novel Method

The present study describes a novel method to improve the dispersibility of silicon nitride powders in aqueous media. Specifically, a new Si3N4@g-C3N4 core–shell composite material was synthesized via annealing the mixture of silicon nitride and melamine under a nitrogen atmosphere using heating method. The effects of various initial mass ratios of Si3N4 and melamine on the structure and dispersibility of the composite were systematically investigated. The results of X-ray photoelectron spectroscopy and transmission electron microscope demonstrated that as-obtained Si3N4@g-C3N4 composite powders possess the core–shell structure, whereas the zeta potential and sedimentation analysis showed that they exhibit good dispersion in aqueous media. Furthermore, the colloidal dispersion of the composite powders is most stable when the initial mass ratio of Si3N4 and melamine is 100:3. The coated g-C3N4 could be completely removed in a cryogenic nitrogen atmosphere. The proposed process is expected to provide novel avenues for the study of dispersion of other inorganic powders.

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