Cleaning of graphene surfaces by low-pressure air plasma

The polymer residues still present on a chemical vapour-deposited graphene surface after its wet transfer by the poly(methyl methacrylate) method to the arbitrary substrates, tend to cause problems such as electrical degradation and unwanted intentional doping. In this study, by using an effective cleaning method for the graphene surface by air-assisted plasma, the graphene surface was cleaned significantly without damaging the graphene network, which resulted in the reduction (approx. 71.11%) of polymer residues on its surface. The analysis reveals that this approach reduced the D-band (impurities, polymer residues) formation while maintaining the π-bonding of the graphene, which affects conductivity. By characterizations of the optical microscope, Raman spectroscopy and atomic force microscopy, we obtained a significantly cleaner graphene surface (roughness of 4.1 nm) compared to pristine graphene (roughness of 1.2 nm) on a SiO 2 substrate. In addition, X-ray photoelectron spectroscopy data revealed that the C1s peak of the air-assisted graphene film was higher than the one of a pristine graphene film, indicating that a cleaner graphene surface was obtained.

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Polystyrene as Graphene Film and 3D Graphene Sponge Precursor

Nanomaterials ◽

10.3390/nano9010101 ◽

2019 ◽

Vol 9 (1) ◽

pp. 101 ◽

Cited By ~ 4

Author(s):

Alejandra Rendón-Patiño ◽

Jinan Niu ◽

Antonio Doménech-Carbó ◽

Hermenegildo García ◽

Ana Primo

Keyword(s):

Thin Film ◽

Atomic Force Microscopy ◽

Photoelectron Spectroscopy ◽

Graphene Film ◽

Visible Absorption ◽

X Ray ◽

3D Graphene ◽

Force Microscopy ◽

Atomic Force ◽

Graphene Sponge

Polystyrene as a thin film on arbitrary substrates or pellets form defective graphene/graphitic films or powders that can be dispersed in water and organic solvents. The materials were characterized by visible absorption, Raman and X-ray photoelectron spectroscopy, electron and atomic force microscopy, and electrochemistry. Raman spectra of these materials showed the presence of the expected 2D, G, and D peaks at 2750, 1590, and 1350 cm−1, respectively. The relative intensity of the G versus the D peak was taken as a quantitative indicator of the density of defects in the G layer.

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Synthesis of Few-Layer Graphene on Copper Using a Low-Cost Atmospheric Thermal Chemical Vapour Deposition System with Methane and Forming Gas

Nano Hybrids ◽

10.4028/www.scientific.net/nh.10.1 ◽

2016 ◽

Vol 10 ◽

pp. 1-13

Author(s):

M.S. Shamsudin ◽

S.J. Fishlock ◽

M. Rusop ◽

S.M. Sanip ◽

Suan Hui Pu

Keyword(s):

Chemical Vapour Deposition ◽

Vapour Deposition ◽

Low Cost ◽

Graphene Film ◽

Chemical Vapour ◽

Force Microscopy ◽

Layer Graphene ◽

Atomic Force ◽

Temperature Deposition ◽

Few Layer Graphene

Graphene has attracted wide interest across a range of applications due to its electrical, mechanical and optical properties. The use of a low-cost, table-top chemical vapour deposition system to deposit few-layer graphene onto copper is reported in this work. Characterisation of the graphene is performed using Raman spectroscopy and atomic force microscopy. The results show that few-layer graphene can be deposited at 1000 °C using CH4 as a carbon precursor, and 5% H2, 95% N2 forming gas as a diluent. The effects of deposition temperature, deposition time, and forming gas addition on graphene film quality was studied experimentally. An increase in graphene quality was observed when forming gas was added during deposition.

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Surface Modification of Polyetheretherketone by Helium/nitrogen and Nitrous Oxide Plasma Enhanced Chemical Vapour Deposition

High Temperature Materials and Processes ◽

10.1515/htmp-2013-0022 ◽

2014 ◽

Vol 33 (2) ◽

pp. 147-153

Author(s):

Stanisława Kluska ◽

Elżbieta Pamuła ◽

Stanisława Jonas ◽

Zbigniew Grzesik

Keyword(s):

Free Energy ◽

Surface Free Energy ◽

Photoelectron Spectroscopy ◽

Sessile Drop ◽

Chemical Vapour ◽

Chemical Vapor ◽

Morphological Characterization ◽

Polar Component ◽

Force Microscopy ◽

Atomic Force

AbstractThe surface of the polyetheretherketone (PEEK) samples was modified by the plasma enhanced chemical vapor deposition (PECVD) in the mixture of He and N2 as well as in the N2O atmosphere. Morphological characterization of the PEEK as well as its surface roughness, chemical structure, and surface free energy were investigated by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and sessile drop technique, respectively. The highest increase in the polar component of the total surface energy was observed for PEEK modified by He+N2 plasma, which correlated with significant increase in the concentration of oxygen and nitrogen-containing chemical functionalities as revealed by XPS. For PEEK submitted to N2O plasma treatment significant changes in surface topography and increase in roughness were observed, but changes in surface chemistry and surface free energy were mild.

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Blue/White Emission from Hydrogenated Amorphous Silicon Carbide Films Prepared by PECVD

MRS Proceedings ◽

10.1557/proc-1153-a16-01 ◽

2009 ◽

Vol 1153 ◽

Cited By ~ 1

Author(s):

Volodymyr Ivashchenko ◽

Andrey Vasin ◽

L. A. Ivashchenko ◽

P. L. Skrynskyy

Keyword(s):

Silicon Carbide ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

Substrate Bias ◽

Double Peak ◽

Hydrogenated Silicon ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

The One

AbstractPhotoluminescence (PL) from hydrogenated silicon carbide (SiC:H) films is studied at room temperature. The films were deposited by plasma-enhanced chemical vapor (PECVD) technique with and without substrate bias using methyltrichlorosilane as a main precursor. After the deposition the samples were annealed at various temperatures in vacuum. The films were characterized by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The samples deposited without substrate bias (series A) were amorphous, whereas the samples deposited with negative substrate bias -100V (series B) were nanocrystalline. The one-peak (470 nm) and double-peak (415 and 437 nm) PL structures of the as-deposited samples A and B were observed, respectively. Annealing strongly enhanced intensity of PL of the samples B and trandformed PL spectrum from double-peak into broad featureless band with intensity at about 470 nm. The blue PL in as-deposited films B is supposed to be assigned to the radiative recombination in the sites located at the nanocrystallite surface, whereas the photo excitation of carries mostly occurs in nanocrystallite cores. A further increase in annealing temperature causes hydrogen effusion, which leads to an increase of the concentration of non-raidative recombination centers associated with dangling-bonds and as a result, to the quenching of PL.

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Tribological Properties of ZrO2 Ceramics under Vacuum Condition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.121 ◽

2010 ◽

Vol 139-141 ◽

pp. 121-124

Author(s):

Rui Peng Tong

Keyword(s):

Photoelectron Spectroscopy ◽

Sliding Wear ◽

Applied Load ◽

High Vacuum ◽

Optical Microscope ◽

Bearing Steel ◽

Vacuum Condition ◽

Force Microscopy ◽

Atomic Force ◽

High Vacuum Condition

Sliding wear was investigated for ZrO2 ceramics against M50 bearing steel under vacuum condition. The research was studied on the ball-disk machine under different loads and steady sliding velocity. The worn surfaces of tested samples were examined using optical microscope, scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. The results showed that the friction coefficient of ZrO2 was decided by the applied load, the critical load of ZrO2 was 10N applied load under vacuum condition, the specific wear rate of ZrO2 drop rapidly with exceeded applied critical loads. The ZrO2 ceramics materials have transferred on the M50 bearing steel surface under high vacuum condition. The dominant wear mechanisms of ZrO2 ceramics were mico-adhesion, tribochemical wear, brittle scraps and micro-furrow wear under vacuum condition.

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Electrosynthesis of polydopamine-ethanolamine films for the development of immunosensing interfaces

Scientific Reports ◽

10.1038/s41598-021-81816-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Luís C. Almeida ◽

Tânia Frade ◽

Rui D. Correia ◽

Yu Niu ◽

Gang Jin ◽

...

Keyword(s):

Protein Interactions ◽

Photoelectron Spectroscopy ◽

Specific Protein ◽

Lower Amount ◽

Force Microscopy ◽

Atomic Force ◽

Electrochemical Approach ◽

One Step ◽

The One ◽

Affinity Interaction

AbstractWe report a straightforward and reproducible electrochemical approach to develop polydopamine-ethanolamine (ePDA-ETA) films to be used as immunosensing interfaces. ETA is strongly attached to polydopamine films during the potentiodynamic electropolymerization of dopamine. The great advantage of the electrochemical methods is to generate the oxidized species (quinones), which can readily react with ETA amine groups present in solution, with the subsequent incorporation of this molecule in the polymer. The presence of ETA and its effect on the electrosynthesis of polydopamine was accessed by cyclic voltammetry, ellipsometry, atomic force microscopy, FTIR and X-ray photoelectron spectroscopy. The adhesive and biocompatible films enable a facile protein linkage, are resilient to flow assays, and display intrinsic anti-fouling properties to block non-specific protein interactions, as monitored by real-time surface plasmon resonance, and confirmed by ellipsometry. Immunoglobulin G (IgG) and Anti-IgG were used in this work as model proteins for the affinity sensor. By using the one-step methodology (ePDA-ETA), the lower amount of immobilized biorecognition element, IgG, compared to that deposited on ePDA or on ETA post-modified film (ePDA/ETA), allied to the presence of ETA, improved the antibody-antigen affinity interaction. The great potential of the developed platform is its versatility to be used with any target biorecognition molecules, allowing both optical and electrochemical detection.

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Characterization of Green Laser Crystallized GeSi Thin Films

MRS Proceedings ◽

10.1557/opl.2011.807 ◽

2011 ◽

Vol 1321 ◽

Author(s):

Balaji Rangarajan ◽

Ihor Brunets ◽

Peter Oesterlin ◽

Alexey Y. Kovalgin ◽

Jurriaan Schmitz

Keyword(s):

Photoelectron Spectroscopy ◽

Chemical Vapour ◽

Green Laser ◽

Laser Crystallization ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Pressure Chemical

ABSTRACTGreen laser crystallization of a-Ge0.85Si0.15 films deposited using Low Pressure Chemical Vapour Deposition is studied. Large grains of 8x2 μm2 size were formed using a location-controlled approach. Characterization is done using Scanning Electron Microscopy, Atomic Force Microscopy, X-Ray Photoelectron Spectroscopy and X-Ray Diffraction.

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Polystyrene as Graphene Film and 3D Graphene Sponge Precursor

10.20944/preprints201811.0437.v1 ◽

2018 ◽

Author(s):

Alejandra Rendón-Patiño ◽

Jinan Niu ◽

Antonio Doménech-Carbó ◽

Hermenegildo García ◽

Ana Primo

Keyword(s):

Thin Film ◽

Photoelectron Spectroscopy ◽

Graphene Film ◽

Visible Absorption ◽

X Ray ◽

3D Graphene ◽

Force Microscopy ◽

Atomic Force ◽

Graphene Films ◽

Graphene Sponge

Polystyrene as a thin film on arbitrary substrates or pellets form defective graphene films or powders that can be dispersed in water and organic solvents. The materials were characterized by visible absorption, Raman and X-ray photoelectron spectroscopy, electron and atomic force microscopy and electrochemistry. Raman spectra of these materials show the presence of the expected 2D, G and D peaks at 2750, 1590 and 1350 cm-1, respectively. The relative intensity of the G vs. the D peak is taken as a quantitative indicator of the density of defects in the G layer.

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Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

MRS Proceedings ◽

10.1557/proc-780-y5.5 ◽

2003 ◽

Vol 780 ◽

Author(s):

C. Essary ◽

V. Craciun ◽

J. M. Howard ◽

R. K. Singh

Keyword(s):

Uv Radiation ◽

Photoelectron Spectroscopy ◽

Grazing Angle ◽

X Ray Diffraction ◽

Metal Thin Films ◽

X Ray ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

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Photocatalytic reduction of graphene oxide with cuprous oxide film under UV-vis irradiation

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2020-0022 ◽

2020 ◽

Vol 59 (1) ◽

pp. 207-214 ◽

Cited By ~ 1

Author(s):

Yao Wang ◽

Jianqing Feng ◽

Lihua Jin ◽

Chengshan Li

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Low Cost ◽

Photocatalytic Reduction ◽

Force Microscopy ◽

Atomic Force ◽

Reduced Graphene ◽

Reduction Efficiency ◽

Metal Organic ◽

Reduction Effect

AbstractWe have grown Cu2O films by different routes including self-oxidation and metal-organic deposition (MOD). The reduction efficiency of Cu2O films on graphene oxide (GO) synthesized by modified Hummer’s method has been studied. Surface morphology and chemical state of as-prepared Cu2O film and GO sheets reduced at different conditions have also been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). Results show that self-oxidation Cu2O film is more effective on phtocatalytic reduction of GO than MOD-Cu2O film. Moreover, reduction effect of self-oxidation Cu2O film to GO is comparable to that of environmental-friendly reducing agent of vitamin C. The present results offer a potentially eco-friendly and low-cost approach for the manufacture of reduced graphene oxide (RGO) by photocatalytic reduction.

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