scholarly journals Electronic Structure of Nitrogen- and Phosphorus-Doped Graphenes Grown by Chemical Vapor Deposition Method

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1173 ◽  
Author(s):  
L. G. Bulusheva ◽  
V. E. Arkhipov ◽  
K. M. Popov ◽  
V. I. Sysoev ◽  
A. A. Makarova ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Xps Spectra ◽  
X Ray ◽  
Nitrogen Doped ◽  
Nexafs Spectroscopy ◽  
Vapor Deposition Technique

Heteroatom doping is a widely used method for the modification of the electronic and chemical properties of graphene. A low-pressure chemical vapor deposition technique (CVD) is used here to grow pure, nitrogen-doped and phosphorous-doped few-layer graphene films from methane, acetonitrile and methane-phosphine mixture, respectively. The electronic structure of the films transferred onto SiO2/Si wafers by wet etching of copper substrates is studied by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy using a synchrotron radiation source. Annealing in an ultra-high vacuum at ca. 773 K allows for the removal of impurities formed on the surface of films during the synthesis and transfer procedure and changes the chemical state of nitrogen in nitrogen-doped graphene. Core level XPS spectra detect a low n-type doping of graphene film when nitrogen or phosphorous atoms are incorporated in the lattice. The electrical sheet resistance increases in the order: graphene < P-graphene < N-graphene. This tendency is related to the density of defects evaluated from the ratio of intensities of Raman peaks, valence band XPS and NEXAFS spectroscopy data.

Synthesis of Crystalline Carbon Nitride by Microwave Plasma Chemical Vapor Deposition

2005 ◽  
Vol 480-481 ◽  
pp. 71-76 ◽  
Author(s):  
Jin Chun Jiang ◽  
Wen Juan Cheng ◽  
Yang Zhang ◽  
He Sun Zhu ◽  
De Zhong Shen
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Carbon Nitride ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Plasma Chemical ◽  
X Ray ◽  
Plasma Chemical Vapor Deposition

Carbon nitride films were grown on Si substrates by a microwave plasma chemical vapor deposition method, using mixture of N2, CH4 and H2 as precursor. Scanning electron microscopy shows that the films consisted of a large number of hexagonal crystallites. The dimension of the largest crystallite is about 3 µm. The X-ray photoelectron spectroscopy suggests that nitrogen and carbon in the films are bonded through hybridized sp2 and sp3 configurations. The X-ray diffraction pattern indicates that the major part of the films is composed of α-, β-, pseudocubic C3N4 and graphitic C3N4. The Raman peaks match well with the calculated Raman frequencies of α- and β-C3N4, revealing the formation of the α- and β-C3N4 phase.

Preparation of Silicon Carbide Nanowires and Nanochains Using Chemical Vapor Deposition Method

2016 ◽  
Vol 697 ◽  
pp. 841-845 ◽  
Author(s):  
Jia Xing Chang ◽  
Rong Zheng Liu ◽  
Ma Lin Liu ◽  
You Lin Shao ◽  
Bing Liu
Keyword(s):  
Silicon Carbide ◽  
Chemical Vapor Deposition ◽  
Electron Microscope ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Raw Material ◽  
Chemical Vapor Deposition Method ◽  
Deposition Method ◽  
X Ray ◽  
Wide Range

Silicon carbide nanowires have been extensively studied because of their unique physical and chemical properties. They can be applied in high temperature, high frequency, high power, and corrosive environments, and have a wide range of applications in electronics, chemical industry, energy and other fields. In this paper, SiC nanowires with high output were synthesized by chemical vapor deposition method using methyltrichlorosilane as raw material. The influences of the catalyst and temperature were studied. SiC nanochains were also obtained by adding Al2O3 powder under appropriate temperature controlled strategy. These two kinds of one-dimensional SiC nanomaterials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and transmission electron microscope (TEM) methods.

Characterization of Nitrogen Doped Diamond Electrodes Produced by Hot Filament Chemical Vapor Deposition

2014 ◽  
Vol 802 ◽  
pp. 180-185 ◽  
Author(s):  
Nazir M. Santos ◽  
Tatiane M. Arantes ◽  
Neidênei G. Ferreira ◽  
Mauricio R. Baldan
Keyword(s):  
Raman Spectroscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Nitrogen Doping ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Diamond Electrodes ◽  
X Ray ◽  
Nitrogen Doped ◽  
Hot Filament

The purpose of this work is to study the structural and morphological modification of the surface of the n-type diamond electrodes as a function of nitrogen doping. The characterizations of these electrodes were made using Raman Spectroscopy, Contact Angle, X-ray diffraction and Scanning Electron Microscopy (SEM). The nitrogen-doped diamond (NDD) electrodes were produced using Hot Filament-assisted Chemical Vapor Deposition method (HFCVD) from methane, hydrogen and nitrogen in the gas mixture. The results from Raman spectroscopy show that the diamond films obtained with nitrogen addition presented one large band at 1100-1700 cm-1. The SEM images showed that the variation in the nitrogen doping influenced the growth rate of films by promoting changes in the sizes of grains from microcrystalline to nanocrystalline texture. This behavior supported the results obtained from X-ray diffraction analyses. It was possible to verify a decrease in the crystallite size as a function of the nitrogen increase.

Doping of boron or nitrogen to multilayered graphene grown on copper by thermal chemical vapor deposition of methane and vapor of phenylboronic acid or melamine

MRS Advances ◽  
2019 ◽  
Vol 4 (3-4) ◽  
pp. 211-216 ◽  
Author(s):  
Ryoko Furukawa ◽  
Yuno Yamamoto ◽  
Yoji Nabei ◽  
Shunji Bandow
Keyword(s):  
Chemical Vapor Deposition ◽  
Raman Scattering ◽  
Sheet Resistance ◽  
Vapor Deposition ◽  
Phenylboronic Acid ◽  
Chemical Vapor ◽  
X Ray ◽  
Thermal Chemical Vapor Deposition ◽  
Nitrogen Doped ◽  
Doped Graphene

AbstractEither boron or nitrogen doped multilayered graphene was prepared by thermal chemical vapor deposition (CVD). Obtained heteroatom doped graphene was examined by Raman scattering, x-ray photo electron spectroscopy (XPS) and temperature dependence of sheet resistance. From the Raman scattering, obvious increase of ID/IG ratio could not be detected by boron doping, while it increased by ∼0.2 or more for nitrogen doped sample. From XPS, doping rates of boron and nitrogen were estimated to be in the range of 5∼12 at% and 1∼2 at%, respectively. XPS also showed that the boron and nitrogen atoms would locate at the doping sites of both graphitic and neighborhood of atomic defect. Magnitude of sheet resistance was decreased by either doping of boron or nitrogen.

Development of highly effective CaO@Al2O3 with hierarchical architecture CO2 sorbents via a scalable limited-space chemical vapor deposition technique

2018 ◽  
Vol 6 (8) ◽  
pp. 3462-3470 ◽  
Author(s):  
Rui Han ◽  
Jihui Gao ◽  
Siyu Wei ◽  
Yanlin Su ◽  
Yukun Qin
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Hierarchical Architecture ◽  
Chemical Vapor Deposition Method ◽  
Deposition Method ◽  
Deposition Technique ◽  
Chemical Vapor Deposition Technique ◽  
Limited Space ◽  
Vapor Deposition Technique

CaO@Al2O3 CO2 sorbents with hierarchical architecture, possessing a highly stable CO2 uptake, have been synthesized using a limited-space chemical vapor deposition method.

THE CHARACTERISTIC OF AS-GROWN AND POST-ANNEALED NITROGEN DOPED AMORPHOUS CARBON THIN FILMS DEPOSITED BY SURFACE WAVE MICROWAVE PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION METHOD

2006 ◽  
Vol 13 (05) ◽  
pp. 593-598
Author(s):  
M. RUSOP ◽  
S. ABDULLAH ◽  
S. ADHIKARI ◽  
A. M. M. OMER ◽  
T. SOGA ◽  
...  
Keyword(s):  
Thin Films ◽  
Chemical Vapor Deposition ◽  
Surface Wave ◽  
Amorphous Carbon ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Plasma Chemical Vapor Deposition ◽  
Nitrogen Doped

Nitrogen doped amorphous carbon ( a - C : N ) thin films were deposited on silicon and quartz substrates by microwave surface-wave plasma chemical vapor deposition (SWMP-CVD) technique at low temperatures (<100°C). We used argon ( Ar ), camphor dissolved in alcohol, and nitrogen ( N ) as carrier, source, and dopant gases, respectively. Optical band gap (E g ) decreased from 4.1 to 2.4 eV when the N gas concentration increased from 0% to 4.5%. The films were annealed at different temperatures ranging from 150°C to 450°C in Ar gas environment to investigate the optical and electrical properties of the films before and after annealing. Both E g and electrical resistivity (ρ) decreased dramatically up to 0.95 eV and 57×103 Ω cm at 450°C annealing. The structural modifications of the films leading them to become more graphitized as a function of the annealing temperature were confirmed by the characterization of Raman spectra.

scholarly journals Fast Formation of Surface Oxidized Zn Nanorods and Urchin-Like Microclusters

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
R. López ◽  
T. Díaz ◽  
G. García ◽  
E. Rosendo ◽  
R. Galeazzi ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Zno Nanorods ◽  
Chemical Vapor ◽  
Deposition Technique ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Vapor Deposition Technique ◽  
Vapor Deposition Technique ◽  
Hot Filament

Entangled Zn-ZnO nanorods and urchin-like microstructures were synthesized by the hot filament chemical vapor deposition technique at 825 and 1015°C, respectively. X-ray diffraction results showed a mixture of ZnO and Zn phases in both nanorods and urchin-like structures. The presence of Zn confirms the chemical dissociation of the ZnO solid source. The Z-ZnO nanorods with diameter of about 100 nm showed dispersed-like morphology. The urchin-like structures with micrometer diameters exhibited porous and rough morphology with epitaxial formation of nanorods.

scholarly journals Magnetic and Electrical Properties of Nitrogen-Doped Multiwall Carbon Nanotubes Fabricated by a Modified Chemical Vapor Deposition Method

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
María Luisa García-Betancourt ◽  
Yadira Itzel Vega-Cantu ◽  
Sofía Magdalena Vega-Díaz ◽  
Aarón Morelos-Gómez ◽  
Mauricio Terrones ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Aqueous Solution ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Morphological Changes ◽  
Multiwall Carbon Nanotubes ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Nitrogen Doped ◽  
Multiwall Carbon

Chemical vapor deposition (CVD) is a preferential method to fabricate carbon nanotubes (CNTs). Several changes have been proposed to obtain improved CNTs. In this work we have fabricated nitrogen-doped multiwall carbon nanotubes (N-MWCNTs) by means of a CVD which has been slightly modified. Such modification consists in changing the content of the by-product trap. Instead of acetone, we have half-filled the trap with an aqueous solution of NaCl (0–26.82 wt.%). Scanning electron microscope (SEM) characterization showed morphological changes depending upon concentration of NaCl included in the trap. Using high resolution transmission electron microscopy several shape changes on the catalyst nanoparticles were also observed. According to Raman spectroscopy results N-MWCNTs fabricated using pure distillate water exhibit better crystallinity. Resistivity measurements performed on different samples by physical properties measurement Evercool system (PPMS) showed metallic to semiconducting temperature dependent transitions when high content of NaCl is used. Results of magnetic properties show a ferromagnetic response to static magnetic fields and the coercive fields were very similar for all the studied cases. However, saturation magnetization is decreased if aqueous solution of NaCl is used in the trap.

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