Fabrication and Characterization of Lanthanum Treated Carboxyl-Graphene Oxide Self-Assembled Composite Film on Silicon Substrate

2016 ◽  
Vol 693 ◽  
pp. 566-575 ◽  
Author(s):  
Da Shu ◽  
Hong Gao ◽  
Da Bin Zhang
Keyword(s):  
Graphene Oxide ◽  
Silicon Substrate ◽  
Photoelectron Spectroscopy ◽  
Multilayer Film ◽  
Film Surface ◽  
Chloroacetic Acid ◽  
Chemical Compositions ◽  
Hydroxyl Groups ◽  
Water Contact ◽  
Micro Electro Mechanical Systems

The admixture of graphene oxide (GO) sheets and chloroacetic acid were ultrasonic treated. As a result, epoxy and hydroxyl groups which existed onto GO sheets were transformed into carboxyl groups. Then, the carboxyl-GO sheets were assembled on silicon substrate by taking use of 3-aminopropyltriethoxysilane (APS) as an intermediate coupling agent (marked as APS-GO). Furthermore, La elements were deposited on the APS-GO by means of chemisorption to form multilayer film (APS-GO-La). Chemical compositions, surface morphologies, and microstructures were investigated by using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and water contact angle (WCA). Experimental results suggested that carboxyl-GO sheets distributed homogeneously on Si substrate. Results also indicated that lanthanum elements can react with the-COOH functional groups of GO film and be adsorbed on the APS-GO film surface. The prepared APS-GO-La multilayer film showed low surface free energy, which has potential applications in nano/micro electro-mechanical systems (N/MEMS).

X-Ray Photoelectron Spectroscopy Study on Reduction of Graphene Oxide with Hydrazine Hydrate

2011 ◽  
Vol 287-290 ◽  
pp. 539-543 ◽  
Author(s):  
Wen Shi Ma ◽  
Jun Wen Zhou ◽  
Xiao Dan Lin
Keyword(s):  
Graphene Oxide ◽  
Hydrazine Hydrate ◽  
Photoelectron Spectroscopy ◽  
Reduction Rate ◽  
Reduction Reaction ◽  
Chemical Compositions ◽  
Total Oxygen ◽  
Graphene Oxides ◽  
X Ray ◽  
Oxygen Groups

Graphene oxide was prepared through Hummers' method，then different reduced graphenes were prepared via reduction of graphene oxide with hydrazine hydrate for 1h、12h and 24h. X-ray photoelectron spectroscopy (XPS) was used for the characterization of graphene oxide and the reduced graphenes. The variation of the contents of carbon in carbon and oxygen functional groups and chemical compositions of graphene oxides were investigated through analysis the content of different carbon atoms in different reduced graphenes. The results showed that the reduction reaction was very fast in the first 1 h, the content of total oxygen bonded carbon atoms decreased from 83.6% to 22.1%, and then after the reduction rate became very slow. After 12h, the content of total oxygen bonded carbon atom is 19.56%, only 2.54% lower than that of 1h’s. At the same time, C-N was introduced in the graphene oxides; this increased the stereo-hindrance for hydrazine hydrate attacking the C-Oxygen groups, thus reduced the reduction rate. After reduction for 24h, there still exists 16.4% oxygen bonded carbon atoms and the total conversion ratio of graphene approaches 70%.

scholarly journals Synthesis of amphiphilic ABA triblock oligomer via ATRP and its surface properties

2017 ◽  
Vol 95 (5) ◽  
pp. 605-611 ◽  
Author(s):  
Lei Wang ◽  
Shaoqing Wen ◽  
Zhanxiong Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Microphase Separation ◽  
Gel Permeation Chromatography ◽  
Contact Angles ◽  
Chemical Compositions ◽  
Water Contact ◽  
Force Microscopy ◽  
Atomic Force ◽  
Poly Ethylene ◽  
Magnetic Resonances

A series of novel amphiphilic ABA-type poly(tridecafluorooctylacrylate)-poly(ethylene glycol)-poly(tridecafluorooctylacrylate) (henceforth referred to as p-TDFA-PEG-p-TDFA) triblock oligomers were successfully synthesized via atom transfer radical polymerization (ATRP) using well-defined Br-PEG-Br as macroinitiator and copper as catalyst. The block oligomers were characterized by Fourier transform infrared (FTIR) spectroscopy and 1H and 19F nuclear magnetic resonances (NMR). Gel permeation chromatography (GPC) showed that the block oligomers have been obtained with narrow molecular weight distributions of 1.22–1.33. X-ray photoelectron spectroscopy (XPS) was carried out to confirm the attachment of p-TDFA-PEG-p-TDFA onto the silicon substrate, together with the chemical compositions of p-TDFA-PEG-p-TDFA. The wetabilities of the oligomer films were measured by water contact angles (CAs). Water CAs of p-TDFA-PEG-p-TDFA film were measured and their morphologies were tested by atomic force microscopy (AFM). The result showed that the CAs of the oligomer films, which possess fluoroalkyl groups assembled on the outer surface, increase after heating due to the migration of fluoroalkyl groups and the resulted microphase separation of the p-TDFA-PEG-p-TDFA.

scholarly journals High Loading Capacity and Wear Resistance of Graphene Oxide/Organic Molecule Assembled Multilayer Film

2021 ◽  
Vol 9 ◽  
Author(s):  
Li Chen ◽  
Gang Wu ◽  
Yin Huang ◽  
Changning Bai ◽  
Yuanlie Yu ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Multilayer Films ◽  
Thickness Measurement ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Film Structure ◽  
Silicon Substrates ◽  
Water Contact ◽  
Macro Scale

Taking advantage of the strong charge interactions between negatively charged graphene oxide (GO) sheets and positively charged poly(diallyldimethylammonium chloride) (PDDA), self-assembled multilayer films of (GO/PDDA)n were created on hydroxylated silicon substrates by alternating electrostatic adsorption of GO and PDDA. The formation and structure of the films were analyzed by means of water contact angle measurement, thickness measurement, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Meanwhile, tribological behaviors in micro- and macro- scale were investigated by AFM and a ball-on-plate tribometer, respectively. The results showed that (GO/PDDA)n multilayer films exhibited excellent friction-reducing and anti-wear abilities in both micro- and macro-scale, which was ascribed to the special structure in (GO/PDDA)n multilayer films, namely, a well-stacked GO–GO layered structure and an elastic 3D crystal stack in whole. Such a film structure is suitable for design molecular lubricants for MEMS and other microdevices.

scholarly journals X-Ray Photoelectron Spectroscopy Study of Silane Coupling Agents/Basalt Fiber Interface

2011 ◽  
Vol 236-238 ◽  
pp. 1467-1471 ◽  
Author(s):  
Ya Lan Liu ◽  
Shi Jie Shen ◽  
Li Zhang ◽  
Ling Min Shao
Keyword(s):  
Coupling Agent ◽  
Photoelectron Spectroscopy ◽  
Silane Coupling Agent ◽  
Basalt Fiber ◽  
Fiber Surface ◽  
Chemical Compositions ◽  
Hydroxyl Groups ◽  
Silane Coupling Agents ◽  
X Ray ◽  
Silane Coupling

In this paper, two types of fiber surface treatment methods, namely heat treatment and chemical coupling, were used to improve the basalt fiber surface properties. The basalt fiber surface was heated under 250Celsius degree for 30minites, and then was treated by silane coupling agent ethanol solution with different concentrations. X-ray photoelectron spectroscopy (XPS) was utilized to study the surface chemical compositions of basalt fiber after treatments. The XPS analysis indicated that chemical bonds between basalt fiber and KH-550 have occurred, and silanols were adsorbed to the surface of basalt fibers by an ether linkage between the silanols and the hydroxyl groups of the fibers. When the concentration of KH-550 is 0.8wt%, the optimal bonding condition is formed between basalt fiber and silane coupling agent.

Construction and surface/interface behavior of bio-functional surface layer by microwave-excited Ar/H2O plasma-induced polyethylene glycol polymerization

2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744093
Author(s):  
Z. Shao ◽  
A. Ogino ◽  
M. Nagatsu
Keyword(s):  
Surface Layer ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Optical Emission ◽  
Aging Effect ◽  
Hydroxyl Groups ◽  
Functional Surface ◽  
Interface Behavior ◽  
Water Contact ◽  
Spacer Layer

Ar/H2O microwave-excited surface-wave plasma-induced grafting-polymerization and crosslinking technique was presented to construct a bio-functional surface layer. Optical emission spectroscopy was used to diagnose Ar/H[Formula: see text]O plasma. The surface/interface behavior especially the aging effect of hydroxyl groups over the grafted PEG spacer layer was investigated by measuring water contact angle and X-ray photoelectron spectroscopy. The results demonstrate that the addition of water vapor into Ar plasma can optimize the concentration of hydroxyl functional groups on surface; grafted PEG spacer layer can provide a long-term hydrophilicity of PU films, and alleviate the aging effect of hydroxyl functional groups.

Etching Characteristics of Low-k Dielectric Using C5H2F10 Liquefied Gas Plasma for Mitigating of Global Warming Potential

2021 ◽  
Vol 13 (9) ◽  
pp. 1764-1770
Author(s):  
Yeonsik Choi ◽  
Jongchan Lee ◽  
Younghun Oh ◽  
Hyun Woo Lee ◽  
Kwang-Ho Kwon
Keyword(s):  
Thin Film ◽  
Dielectric Constant ◽  
Plasma Etching ◽  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Film Surface ◽  
Chemical Compositions ◽  
Nanoscale Devices ◽  
Mixed Gas ◽  
Gas Plasma

In this work, we studied the etch characteristics and dielectric constant change of SiOC thin films by plasma etching for the fabrication of nanoscale devices to evaluate the C5H2F10 as alternative etching gas. We performed plasma etching of SiOC films with inductively coupled plasma using the CF4+X+O2 mixed gas, where X = CHF3 and C5H2F10. Plasma diagnosis such as optical emission spectroscopy and double Langmuir probe measurements were carried. We analyzed the chemical compositions of residues on the etched SiOC film surface using X-ray photoelectron spectroscopy. After the process, contact resistance was measured using the transmission line method to analyze the degree of polymer on the surface of the silicon. Ellipsometry were used to evaluate the change in the dielectric constant of the thin film due to plasma exposure. It was confirmed that the etched profile was more vertical than that of the CHF3 gas plasma, and the increase in the dielectric constant of the SiOC thin film by C5H2F10 gas plasma is less than that of CHF3 gas plasma. These results confirmed that C5H2F10 gas was a powerful alternative to CHF3 gas in semiconductor processing for the fabrication of nanoscale devices.

scholarly journals Plasma Etching Behavior of SF6 Plasma Pre-Treatment Sputter-Deposited Yttrium Oxide Films

Coatings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 637
Author(s):  
Wei-Kai Wang ◽  
Sung-Yu Wang ◽  
Kuo-Feng Liu ◽  
Pi-Chuen Tsai ◽  
Yu-Hao Zhang ◽  
...  
Keyword(s):  
Yttrium Oxide ◽  
Plasma Etching ◽  
Photoelectron Spectroscopy ◽  
Film Surface ◽  
Chemical Compositions ◽  
Plasma Irradiation ◽  
Fluorocarbon Plasma ◽  
Sulfur Fluoride ◽  
Pre Treatment ◽  
Sputter Deposited

Yttrium oxyfluoride (YOF) protective materials were fabricated on sputter-deposited yttrium oxide (Y2O3) by high-density (sulfur fluoride) SF6 plasma irradiation. The structures, compositions, and fluorocarbon-plasma etching behaviors of these films were systematically characterized by various techniques. After exposure to SF6 plasma, the Y2O3 film surface was fluorinated significantly to form a YOF film with an approximate average thickness of 30 nm. X-ray photoelectron spectroscopy revealed few changes in the elemental and chemical compositions of the surface layer after fluorination, confirming the chemical stability of the YOF/Y2O3 sample. Transmission electron microscopy confirmed a complete lattice pattern on the YOF/Y2O3 structure after fluorocarbon plasma exposure. These results indicate that the SF6 plasma-treated Y2O3 film is more erosion resistant than the commercial Y2O3 coating, and thus accumulates fewer contamination particles.

scholarly journals Effect of Sputtering Temperature on Fluorocarbon Films: Surface Nanostructure and Fluorine/Carbon Ratio

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 848 ◽  
Author(s):  
Qi Zhao ◽  
Feipeng Wang ◽  
Kaizheng Wang ◽  
Guibai Xie ◽  
Wanzhao Cui ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Target Material ◽  
Chemical Compositions ◽  
Water Contact ◽  
Force Microscopy ◽  
Fluorocarbon Films ◽  
Atomic Force ◽  
Surface Nanostructure ◽  
Deposited Film ◽  
Fluorocarbon Film

In this work, fluorocarbon film was deposited on silicon (P/100) substrate using polytetrafluoroethylene (PTFE) as target material at elevated sputtering temperature. Field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to investigate the surface morphology as well as structural and chemical compositions of the deposited film. The surface energy, as well as the polar and dispersion components, were determined by water contact angle (WCA) measurement. The experimental results indicated that increasing sputtering temperature effectively led to higher deposition rate, surface roughness and WCA of the film. It was found that the elevated temperature contributed to increasing saturated components (e.g., C–F2 and C–F3) and decreasing unsaturated components (e.g., C–C and C–CF), thus enhancing the fluorine-to-carbon (F/C) ratio. The results are expected aid in tailoring the design of fluorocarbon films for physicochemical properties.

scholarly journals Surface Segregation of Amphiphilic PDMS-Based Films Containing Terpolymers with Siloxane, Fluorinated and Ethoxylated Side Chains

Coatings ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 153 ◽  
Author(s):  
Elisa Martinelli ◽  
Elisa Guazzelli ◽  
Antonella Glisenti ◽  
Giancarlo Galli
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Segregation ◽  
Water Environment ◽  
Film Surface ◽  
Side Chain ◽  
Chemical Compositions ◽  
Side Chains ◽  
Air Interface ◽  
High Enrichment ◽  
Surface Active

(Meth)acrylic terpolymers carrying siloxane (Si), fluoroalkyl (F) and ethoxylated (EG) side chains were synthesized with comparable molar compositions and different lengths of the Si and EG side chains, while the length of the fluorinated side chain was kept constant. Such terpolymers were used as surface-active modifiers of polydimethylsiloxane (PDMS)-based films with a loading of 4 wt%. The surface chemical compositions of both the films and the pristine terpolymers were determined by angle-resolved X-ray photoelectron spectroscopy (AR-XPS) at different photoemission angles. The terpolymer was effectively segregated to the polymer−air interface of the films independent of the length of the constituent side chains. However, the specific details of the film surface modification depended upon the chemical structure of the terpolymer itself. The exceptionally high enrichment in F chains at the surface caused the accumulation of EG chains at the surface as well. The response of the films to the water environment was also proven to strictly depend on the type of terpolymer contained. While terpolymers with shorter EG chains appeared not to be affected by immersion in water for seven days, those containing longer EG chains underwent a massive surface reconstruction.

Preparation and Characterization of Plasma-Treated Porous Poly(glycerol sebacate) Scaffolds

2013 ◽  
Vol 747 ◽  
pp. 182-185
Author(s):  
Tharinee Theerathanagorn ◽  
Boonlom Thavornyutikarn ◽  
Wanida Janvikul
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Average Molecular Weight ◽  
Sebacic Acid ◽  
Angle Measurement ◽  
Porous Scaffolds ◽  
Hydroxyl Groups ◽  
Condensation Polymerization ◽  
Water Contact

In this study, poly (glycerol sebacate) (PGS) was initially synthesized via condensation polymerization of glycerol and sebacic acid at equimolar ratio (1:1) at 130°C for 24 h. The number average molecular weight (Mn) of the resulting polymer determined by gel permeation chromatography (GPC) was about 2800 g/mol. Porous PGS scaffolds were subsequently prepared by a particle-leaching technique. NaCl was added into the polymer at 60-90% w/w; the mixtures were cured in Teflon molds at 140°C for 16 h. The porous scaffolds were further subjected to surface treatment with low pressure oxygen plasma to increase surface carboxyl and hydroxyl groups and thereby enhance hydrophilicity of PGS scaffold surface. The surface morphology and wettability of both untreated PGS and plasma-treated PGS scaffolds were comparatively determined by scanning electron microscopy (SEM) and water contact angle measurement, respectively. A considerable decrease in water contact angle was observed on the PGS scaffolds after the plasma treatment. The surface chemistry, mechanical strength and degree of swelling of the PGS scaffolds were also assessed by X-ray photoelectron spectroscopy (XPS), dynamic mechanical analysis (DMA) and swelling measurement, respectively.

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