Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Growth kinetics of white graphene (h-BN) on a planarised Ni foil surface.

ABSTRACT: The morphology of the surface and the grain orientation of metal catalysts have been considered to be two important factors for the growth of white graphene (h-BN) by chemical vapour deposition (CVD). We report a correlation between the growth rate of h-BN and the orientation of the nickel grains. The surface of the nickel (Ni) foil was first polished by electrochemical polishing (ECP) and subsequently annealed in hydrogen at atmospheric pressure to suppress the effect of the surface morphology. Atmospheric annealing with hydrogen reduced the nucleation sites of h-BN, which induced a large crystal size mainly grown from the grain boundary with few other nucleation sites in the Ni foil. A higher growth rate was observed from the Ni grains that had the {110} or {100} orientation due to their higher surface energy.

SUBMITTER: Cho H

PROVIDER: S-EPMC4496663 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Growth kinetics of white graphene (h-BN) on a planarised Ni foil surface.

Cho Hyunjin H Park Sungchan S Won Dong-Il DI Kang Sang Ook SO Pyo Seong-Soo SS Kim Dong-Ik DI Kim Soo Min SM Kim Hwan Chul HC Kim Myung Jong MJ

Scientific reports 20150709

The morphology of the surface and the grain orientation of metal catalysts have been considered to be two important factors for the growth of white graphene (h-BN) by chemical vapour deposition (CVD). We report a correlation between the growth rate of h-BN and the orientation of the nickel grains. The surface of the nickel (Ni) foil was first polished by electrochemical polishing (ECP) and subsequently annealed in hydrogen at atmospheric pressure to suppress the effect of the surface morphology. ...[more]

PMID: 26156068

Similar Datasets

Tuning adlayer-substrate interactions of graphene/h-BN heterostructures on Cu(111)-Ni and Ni(111)-Cu surface alloys.

Project description:The evolution of the interface and interaction of h-BN and graphene/h-BN (Gr/h-BN) on Cu(111)-Ni and Ni(111)-Cu surface alloys versus the Ni/Cu atomic percentage on the alloy surface were comparatively studied by the DFT-D2 method, including the critical long-range van der Waals forces. Our results showed that the interaction strength and interface distance of Gr/h-BN/metal can be distinctly tuned by regulating the chemical composition of the surface alloy at the interface. The initially weak interaction of h-BN/Cu(111)-Ni increased linearly with increasing Ni atomic percentage, and the interface distances decreased from ∼3.10 to ∼2.10 Å. For the h-BN/Ni(111)-Cu interface, the strong interaction of the NtopBfcc/hcp stacking decreased sharply with increasing Cu atomic percentage from 0% to 50%, and the interface distances increased from ∼2.15 to ∼3.00 Å; meanwhile, the weak interaction of the BtopNfcc/hcp stacking decreased slightly with increasing Cu atomic percentage. The absorption of graphene on h-BN/Cu(111)-Ni with BtopNhollow/NtopBfcc and BtopNhollow/BtopNfcc stacking was more energetically favorable than that with NtopBhollow/NtopBfcc and NtopBhollow/BtopNfcc at Ni atomic percentages under 75%, while the interaction energy of graphene on h-BN/Cu(111)-Ni increased sharply at Ni atomic percentages higher than 75% for the BtopNhollow/NtopBfcc and NtopBhollow/NtopBfcc stacking. In contrast, the interaction between graphene and the h-BN/Ni(111)-Cu surface increased sharply at Cu atomic percentages lower than 25% and decreased sharply at Cu atomic percentages higher than 75%. The interaction energies were higher when the percentage of Cu atom was between 25% and 75%. The analysis of charge transfer and density of states provided further details on the changing character and evolution trends of the interactions among graphene, h-BN, and Cu-Ni surface alloy versus the Ni/Cu atomic percentage.

| S-EPMC8693814 | biostudies-literature

Role of Precursor Carbides for Graphene Growth on Ni(111).

Project description:Surface X-ray Diffraction was used to study the transformation of a carbon-supersaturated carbidic precursor toward a complete single layer of graphene in the temperature region below 703?K without carbon supply from the gas phase. The excess carbon beyond the 0.45? monolayers of C atoms within a single Ni2C layer is accompanied by sharpened reflections of the |4772| superstructure, along with ring-like diffraction features resulting from non-coincidence rotated Ni2C-type domains. A dynamic Ni2C reordering process, accompanied by slow carbon loss to subsurface regions, is proposed to increase the Ni2C 2D carbide long-range order via ripening toward coherent domains, and to increase the local supersaturation of near-surface dissolved carbon required for spontaneous graphene nucleation and growth. Upon transformation, the intensities of the surface carbide reflections and of specific powder-like diffraction rings vanish. The associated change of the specular X-ray reflectivity allows to quantify a single, fully surface-covering layer of graphene (2?ML?C) without diffraction contributions of rotated domains. The simultaneous presence of top-fcc and bridge-top configurations of graphene explains the crystal truncation rod data of the graphene-covered surface. Structure determination of the |4772| precursor surface-carbide using density functional theory is in perfect agreement with the experimentally derived X-ray structure factors.

| S-EPMC5805774 | biostudies-literature

Ni Nanoparticles on the Reduced Graphene Oxide Surface Synthesized in Supercritical Isopropanol.

Project description:Nanocomposites based on ferromagnetic nickel nanoparticles and graphene-related materials are actively used in various practical applications such as catalysis, sensors, sorption, etc. Therefore, maintaining their dispersity and homogeneity during deposition onto the reduced graphene oxide substrate surface is of crucial importance to provide the required product characteristics. This paper demonstrates a new, reproducible method for preparing a tailored composite based on nickel nanoparticles on the reduced graphene oxide surface using supercritical isopropanol treatment. It has been shown that when a graphene oxide film with previously incorporated Ni2+ salt is treated with isopropanol at supercritical conditions, nickel (2+) is reduced to Ni (0), with simultaneous deoxygenation of the graphene oxide substrate. The resulting composite is a solid film exhibiting magnetic properties. XRD, FTIR, Raman, TEM, and HRTEM methods were used to study all the obtained materials. It was shown that nickel nanoparticles on the surface of the reduced graphene oxide had an average diameter of 27 nm and were gradually distributed on the surface of reduced graphene oxide sheets. The data obtained allowed us to conduct a reconnaissance discussion of the mechanism of composite fabrication in supercritical isopropanol.

| S-EPMC10674343 | biostudies-literature

Hall sensors batch-fabricated on all-CVD h-BN/graphene/h-BN heterostructures.

Project description:The two-dimensional (2D) material graphene is highly promising for Hall sensors due to its potential of having high charge carrier mobility and low carrier concentration at room temperature. Here, we report the scalable batch-fabrication of magnetic Hall sensors on graphene encapsulated in hexagonal boron nitride (h-BN) using commercially available large area CVD grown materials. The all-CVD grown h-BN/graphene/h-BN van der Waals heterostructures were prepared by layer transfer technique and Hall sensors were batch-fabricated with 1D edge metal contacts. The current-related Hall sensitivities up to 97 V/AT are measured at room temperature. The Hall sensors showed robust performance over the wafer scale with stable characteristics over six months in ambient environment. This work opens avenues for further development of growth and fabrication technologies of all-CVD 2D material heterostructures and allows further improvements in Hall sensor performance for practical applications.

| S-EPMC5680335 | biostudies-literature

Continuous Growth of Highly Reproducible Single-Layer Graphene Deposition on Cu Foil by Indigenously Developed LPCVD Setup.

Project description:Continuous growth of high-quality single-layer graphene (SLG) is highly desirable in several electronic and optoelectronic applications. To fulfill such requirements, we proposed a low-cost, highly reproducible high-quality SLG synthesized by indigenously developed low-pressure chemical vapor deposition (LPCVD) setup. The quality of SLG is examined by Raman spectroscopy, where we have probed the I 2D/I G ratio for continuous 30 runs to assess the reproducibility and quality of single-layer using proposed indigenous LPCVD setup for device fabrication. The highest I 2D/I G ratio of SLG (5.82) was found with full width at half maximum values of 2D peak and G peak of ∼30.10 cm-1 and ∼20.86 cm-1, respectively. Further, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy have been performed to study the quality of SLG. Thickness measurement of graphene with graphene grain size is calculated from atomic force microscopy studies, and the average grain size is found to be 1-3 μm. Moreover, I-V characteristics have also been investigated by the two-probe method to ensure the quality of SLG. The lowest resistance of the SLG (∼387 Ω) was found at room temperature. Thus, this new indigenously developed low-cost setup provides a novel alternative method to produce highly reproducible metrology-grade continuous SLG on Cu substrate for next-generation quantum devices.

| S-EPMC6648755 | biostudies-literature

Interfacial Strength and Surface Damage Characteristics of Atomically Thin h-BN, MoS<sub>2</sub>, and Graphene.

Project description:Surface damage characteristics of single- and multilayer hexagonal boron nitride (h-BN), molybdenum disulfide (MoS2), and graphene films were systematically investigated via atomic force microscopy (AFM)-based progressive-force and constant-force scratch tests and Raman spectroscopy. The film-to-substrate interfacial strengths of these atomically thin films were assessed based on their critical forces (i.e., the normal force where the atomically thin film was delaminated from the underlying substrate), as determined from progressive-force scratch tests. The evolution of surface damage with respect to normal force was further investigated using constant-force tests. The results showed that single-layer h-BN, MoS2, and graphene strongly adhere to the SiO2 substrate, which significantly improves its tribological performance. Moreover, defect formation induced by scratch testing was found to affect the topography and friction force differently prior to failure, which points to distinct surface damage characteristics. Interestingly, the residual strains at scratched areas suggest that the scratch test-induced in-plane compressive strains were dominant over tensile strains, thereby leading to buckling in front of the scratching tip and eventually failure at sufficient strains. These trends represent the general failure mechanisms of atomically thin materials because of a scratch test. As the number of layers increased, the tribological performances of atomically thin h-BN, MoS2, and graphene were found to significantly improve because of an increase in the interfacial strengths and a decrease in the surface damage and friction force. In all, the findings on the distinctive surface damage characteristics and general failure mechanisms are useful for the design of reliable, protective and solid-lubricant coating layers based on these materials for nanoscale devices.

| S-EPMC5969908 | biostudies-literature

Decomposition of Cyclohexane on Ni₃Al Thin Foil Intermetallic Catalyst.

Project description:Micro-grained thin foils made of Ni₃Al intermetallic alloy were fabricated, according to a previously described procedure, and tested as catalyst for decomposition of cyclohexane. The conversion efficiency of the catalyst was evaluated in a synthetic air atmosphere, and found to be as high as 98.7% ± 1.0% at 600 °C and 86.7% ± 3.6% at 500 °C. During the reaction, the growth of carbon nanofibers on the catalysts surface was observed. The chemical and phase composition of the nanofibers was investigated with scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), finding them to be made of graphitic carbon. Additionally, nanoparticles of nickel appear to be incorporated in the fibers. The obtained material is promising for large scale fabrication in industrial applications because of its high efficiency in the hydrocarbon decomposition, the simple fabrication procedure, and the form of self-supporting foils with the presence of additional carbon nanofibers that increase its efficiency.

| S-EPMC5456010 | biostudies-other

Growth of Graphene/h-BN Heterostructures on Recyclable Pt Foils by One-Batch Chemical Vapor Deposition.

Project description:High-quality large-area graphene/h-BN vertical heterostructures are promising building blocks for many viable applications such as energy harvesting/conversion, electronics and optoelectronics. Here, we successfully grew high-quality large-area graphene/h-BN vertical heterostructures on Pt foils by one-batch low-pressure chemical vapor deposition (LPCVD). We obtained the high quality of about 200-µm-wide graphene/h-BN film having uniform layer thickness. Moreover, the obtained graphene/h-BN heterostructures exhibited field effect mobility of up to 7,200 cm2V-1s-1 at room temperature. These results suggest that such graphene/h-BN heterostructures on recyclable Pt foils grown by LPCVD are promising for high-performance graphene-based electronics.

| S-EPMC5719054 | biostudies-literature

In-situ epitaxial growth of graphene/h-BN van der Waals heterostructures by molecular beam epitaxy.

Project description:Van der Waals materials have received a great deal of attention for their exceptional layered structures and exotic properties, which can open up various device applications in nanoelectronics. However, in situ epitaxial growth of dissimilar van der Waals materials remains challenging. Here we demonstrate a solution for fabricating van der Waals heterostructures. Graphene/hexagonal boron nitride (h-BN) heterostructures were synthesized on cobalt substrates by using molecular beam epitaxy. Various characterizations were carried out to evaluate the heterostructures. Wafer-scale heterostructures consisting of single-layer/bilayer graphene and multilayer h-BN were achieved. The mismatch angle between graphene and h-BN is below 1°.

| S-EPMC4595826 | biostudies-literature

Surface tension determines tissue shape and growth kinetics.

Project description:The collective self-organization of cells into three-dimensional structures can give rise to emergent physical properties such as fluid behavior. Here, we demonstrate that tissues growing on curved surfaces develop shapes with outer boundaries of constant mean curvature, similar to the energy minimizing forms of liquids wetting a surface. The amount of tissue formed depends on the shape of the substrate, with more tissue being deposited on highly concave surfaces, indicating a mechano-biological feedback mechanism. Inhibiting cell-contractility further revealed that active cellular forces are essential for generating sufficient surface stresses for the liquid-like behavior and growth of the tissue. This suggests that the mechanical signaling between cells and their physical environment, along with the continuous reorganization of cells and matrix is a key principle for the emergence of tissue shape.

| S-EPMC6739108 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data