bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Study on Contamination Control of Fume By Analyzation of Air Current
Authors: Lee Sunghoon , Kim Byungsu , Park Segeun , Choi Sanghyun , Yoon Taeyang 
Published: February 2020

Fume is major pollution source which is occurred after etch process. [1] Fig. 1 is shown how fume is exhausted after etch process. And wafer stay in buffer during exhausting. At this time, this fume is absorbed with surface of wafer or remained on surface of wafer. Additionally, this fume combines with atmospheric moisture in air. And it is changed to particle the diameter of this particle is less than 1um. So, this fume often make serious wafer defect. For these reasons, if we cannot control this fume, product quality and wafer yield is seriously decreased. Moreover, it makes productivity issues because we spend a lot of time for fume removal process of defected equipments like fig 1. So, our paper proposes several optimization methods for ‘out buffer system’.
Firstly, several gases stay in exhaust system like fig 2(a). This analysis is use aero-dynamics simulation for traditional exhaust systems. This result of simulation is shown some gas stay in system. This gas is normally changed to fume. For reducing this remained gas, we change diameter of vacuum line like fig 4. It shows our final optimized system. Major optimization of systems that the diameter of vacuum line is changed from 200 Ø to 100 Ø. To choose this optimized diameter, we use Bernoulli's theorem [2]. Fig 3 shows that two output vacuum lines are connected to same direct line. So there are different pressures in vacuum line. This is the reason why turbulence flow occurred. To find optimal diameter of this exhaust pipe line, we use Bernoulli's theorem simulation with various test design. Finally we found a optimal structure of vacuum line.
REFERENCE
1. Effects of reactant rotational excitation on reactivity: Perspectives from the sudden limit B Jiang, J Li, H Guo - The Journal of chemical physics, 2014 - scitation.aip.org
2. Department of Mathematics, Hoseo University, Chungnam 336-795, Korea *School of Mechanical Engineering

Figure 1
An Assessment of Copper Electrodeposition into Bakky-Pepar Consisted of Single-Walled Carbon Nanotube
Authors: Kirihata Kyohei , Arai Susumu , Katada Arinobu , Hirota Mitsuhito , Uejima Mitsugu 
Published: February 2020

Introduction

Copper has many useful properties, such as high electrical conductivity, good thermal conductivity and ductility, resulting in the widespread use of copper plating in an electronics industry. Single-walled carbon nanotubes (SWCNTs) also exhibit attractive characteristics, including stable electrical resistance in the presence of high currents, superior thermal conductivity and good field emission properties, and so have a wide range of applications. Cu/SWCNT composites are also expected to exhibit excellent electrical and thermal conductivities. In the present research, we attempted to fabricate a novel Cu/SWCNT composite by copper deposition into Bakky-paper consisted of SWCNTs.

Experimental

Bakky-paper (SWCNT sheet) with a thickness in the range of 30 to 40 mm (Zeon Co.) was used as the cathode, and copper electrodeposition was performed on both sides under galvanostatic conditions with an immersed surface area of 2 cm2(= 1 cm × 1 cm × 2). Copper containing phosphorous as anodes were placed at both sides of the cathode, and then copper deposition was carried out with or without additives. The additives were polyethylene glycol (PEG), chloride ions, bis(3-sulfopropyl) disulfide (SPS) and Janus green B (JGB). The surfaces and cross-sectional morphologies of the composites obtained by the electrodeposition were observed by a field emission scanning electron microscopy (FE-SEM). The effects of plasma pretreatment of the Bakky-paper (SWCNT sheet) on microstructure and copper deposition were also examined.

Results and Discussion

Figure 1 compares cross-sectional SEM images of Cu/SWCNT composites prepared by two kinds of electrodeposition bath. Figure 1(a) displays the composite prepared in a bath without additives. It is clear that copper plating proceeded only on Bakky-paper surface. This is the reason why the plating liquid could not penetrate the sheet. In contrast, the use of various additives in the plating bath (100 ppm PEG + 50 ppm Cl- + 2 ppm SPS + 2 ppm JGB) resulted in copious copper deposition within the sheet structure (Figure 1(b)). Electrodeposition under these conditions also generated numerous voids in the Cu/SWCNT composite and greatly increased the thickness of the SWCNT sheet. The application of the Cu/SWCNT composite-film would be effective for the development of electronics devices.

Figure 1
Solid Oxide Photo-electrochemistry with Oxides “Breathing” upon UV Light and Solar Cells Operating at 400°C
Authors: Fleig Juergen , Walch Gregor , Opitz Alexander Karl , Kubicek Markus , Brunauer Georg Christoph , Rotter Bernhard , Ponweiser Karl 
Published: February 2020

Photo-electrochemistry is largely based on aqueous electrolytes. However, the efficiency and/or materials stability in such cells is still not sufficient for widespread application. This raises the question whether solid electrolyte based systems may also be an option. Very little is known on the realizability of all solid state photo-electrochemical cells based on oxide ion conductors; UV light was shown to accelerate oxygen incorporation into SrTiO3 [1] and a theoretical model of a solid state photo-electrochemical cell including a mixed conducting electrode was described in Ref. [2]. Here, we present experiments of two novel approaches to solid oxide photo-electrochemical cells.
SrTiO3 with Pt current collector was used as an electrode on an oxide ion conductor (YSZ). Upon UV light, cell voltages in the 200 mV range result at ca. 400°C. Oxygen incorporation of the illuminated SrTiO3, i.e. a kind of “breathing” of the electrode, modifies the voltage and an EMF remains even after switching off the light. Two effects take place: a photo-voltage develops, which is coupled to the external circuit via a solid electrolyte, and a battery-type (Nernst) voltage builds up upon illumination. The latter reflects the oxygen chemical potential difference induced by the “breathing” of the oxide and corresponds to a kind of light driven-battery charging.
A second approach makes use of a high temperature solar cell which consists of a Sr-doped LaCrO3 thin film on a SrTiO3 single crystal. This heterojunction leads to photo-voltages as high as 900 mV at 400°C [3]. The photon induced driving force was then used to pump oxygen from low to high oxygen partial pressures and thus to chemically store photon energy [3]. In the corresponding solid oxide photo-electrochemical cell, the bottom electrode of the oxide solar cell (Sr-doped LaFeO3) was employed as the top electrode of a zirconia based solid electrochemical cell. By short circuiting the outer electrodes of this oxide hetero-structure electrochemical oxygen pumping became possible.
[1] X. Ye, J. Melas-Kyriazi, Z. A. Feng, N. A. Melosh, W. C. Chueh, Phys. Chem. Chem. Phys. 2013, 15, 15459-15469.
[2] R. Merkle, R.A. De Souza, J. Maier, Angew. Chem. Int. Ed. 2001, 40, 2126-2129
[3] G. C. Brunauer, B. Rotter, G. Walch, A. K. Opitz, G. Ponweiser, J. Summhammer, J. Fleig, Adv. Funct. Mat. 26 (2016) 120-128
(Invited) Differntiating the Behaviour of Electrochemical Capacitor Materials
Authors: Donne Scott W , Dupont Madeleine F 
Published: February 2020

Electrochemical capacitors are rapidly emerging as a viable energy storage technology for many different applications, encompassing a wide range of size scales. Their performance is typified by a high power density and excellent cyclability, as well as a relatively low energy density, improving which has been the focus of considerable research activity. Environmental considerations and cost per unit of energy are also important for widespread commercial acceptance.
During the quest for development of an improved electrochemical system many different materials have been examined for electrode use. Most often activated carbon is the material of choice for electrochemical capacitors, in particular when coupled with a non-aqueous electrolyte based on either acetonitrile, propylene carbonate, or perhaps even an ionic liquid. Improving the performance of the activated carbon has been an important avenue of research, in particular optimizing the pore size distribution of the material to enable maximum charge storage in the electrical double layer. Other avenues of research have focused on developing other classes of materials, such as metal oxides and conducting polymers, so as to store charge via pseudo-capacitance, which can be defined as facile, reversible redox reactions occurring at the electrode-electrolyte interface. In this way, the near-surface region of the electrode material can be accessed for what is effectively pseudo-3D charge storage.
The study of materials that exhibit pseudo-capacitance has enabled many materials previously considered as battery materials, to make in-roads into electrochemical capacitor applications. While the concept and study of pseudo-capacitive materials is very worthwhile for electrochemical capacitor applications, there is growing interest in highlighting the differences in charge storage mechanisms that occur in these materials, particularly so since the end electrochemical result is very similar even though the choice of materials and notional charge storage mechanisms are very different.
This presentation will highlight the differences in materials used, as well as differentiate the charge storage mechanisms that various materials undergo. The presentation will also seek to describe how materials can exhibit battery-like behaviour under one set of conditions, and electrochemical capacitor-like behaviour under others.
Mechanism Study on the Asymmetric Behaviors of Carbon/Carbon Supercapacitors
Authors: Hu Lintong , Li Huiqiao 
Published: February 2020

Electrical double layer capacitors (EDLCs) have attracted tremendous attention for their high power density, long cycle life, excellent stability and fast charge-discharge rate. Due to the high surface area, good conductivity, and high chemical stability in different solutions, many efforts are devoted to explore carbon-based materials for EDLCs. However, a common phenomenon that the positive and negative electrodes have unequal capacitance in carbon/carbon supercapacitors has not received the deserved attention. [1, 2] The asymmetric capacitance limits the potential window and hence the cell energy density. [3,4] By smart balancing the asymmetric behaviors of the positive and negative electrodes, a higher energy density can be expected for supercapacitors without additional cost. Thus the mechanism study on the asymmetric phenomenon is of great meaning to achieve high performance supercapacitors.
We studied the capacitive behaviors of the positive and negative electrode in a carbon/carbon supercapacitor respectively by using both experimental measurements and molecular dynamics calculations. Two different electrolytes, tetraethylammonium tetrafluoroborate (TEABF4) and lithium hexafluorophosphate (LiPF6) in propylene carbonate (PC), were used for the identical carbon electrodes. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) tests show that the two electrodes in a capacitor not only exhibit different specific capacitance but also work in different width of voltage window. Theoretical calculations give a full explanation of the experiment observations, which indicate that the size of solvated ions, the diffusion property and the solvation energy play important roles in such asymmetric behaviors. The results help to get a deep understanding of factors involved in the charge storage mechanism and can provide guidance for designing appropriate carbon-electrolyte system for EDLCs.

References

[1] Chmiola, J.; Largeot, C.; Taberna, P. L.; Simon, P.; Gogotsi, Y.; Angew. Chem. Int. Ed. 2008, 47, 3392.
[2] Wang, H.; Forse, A. C.; Griffin, J. M.; Trease, N. M.; Trognko, L.; Taberna, P. L.; Simon, P.; Grey, C. P.; J. Am. Chem. Soc.
2013, 135, 18968.
[3] Weng, Z.; Li, F.; Wang, D. W.; Wen, L.; Cheng, H. M.; Angew. Chem. Int. Ed.
2013, 52, 3722.
[4] Aken, K. L. V.; Beidaghi, M.; Gogotsi, Y.; Angew. Chem. Int. Ed. 2015, 54, 4806-4809.

Figure 1
Silica-Based Ionogel Electrolyte for Electrical Double Layer Capacitors
Authors: Negre Léo , Daffos Barbara , Taberna Pierre-Louis , Simon Patrice 
Published: February 2020

Electrochemical Capacitors (ECs), also known as supercapacitors, have now reached the technical maturity for complementing- and sometimes replacing- batteries in a broad range of applications. Conventional electrolytes based on acetonitrile or propylene carbonate solvents have been mainly used in combination with ammonium cations and fluoride anions. Designing solid electrolytes for ECs would be of great interest in the aim of solving packaging issues, corrosion, self-discharge or leaks. Moreover these solid electrolytes could be used for flexible supercapacitors applications.
Ionogels are quasi-solid electrolyte obtained from the trapping of an IL into a silica scaffold using a sol-gel process. The first part of our work has been devoted to a better understanding of the non-hydrolytic sol-gel mechanisms occurring during the formation of ionogels, using electrochemical impedance spectroscopy. Change of the conductivity of the sol-gel mixture (a Formic acid and Tetraethyl orthosilicate mixture) shows two different time domains. The mixture conductivity is first decreasing drastically during the first 25 minutes of the sol-gel process, assuming to originate from the in-situ generation of water through esterification reaction. In the second time range (t>25 min), the conductivity tends to level off, associated with a series of chemical reactions. More details about this study will be added during the presentation.
In a second part of the talk, we will show the electrochemical performance of an supercapacitors cell assembled with activated carbon as active materials and an ionogel electrolyte containing an ionic liquid mixture (1:1 by weight or molar ratio) of N-methyl-N-propylpiperidinium bis(fluorosulfonyl)imide (PIP13FSI) and N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14FSI). Cyclic voltammetries and electrochemical impedance spectroscopy plots in a large temperature range (-40°C to +60°C) will be presented and discussed. The ionogel exhibits a high ionic conductivity over a wide temperature range (from 0.2 mS.cm−1 at −40 °C up to 10 mS.cm−1 at 60 °C). The ionogel-based supercapacitor using two activated carbon electrodes can be operated over 3 V cell voltage window. Moreover this all solid-supercapacitor shows a capacitance up to 90 F.g−1 at room temperature. These encouraging results show the interest of developing such devices, including non-toxic and safer electrolytes, packaging issues and flexible devices development.
Gallium Catalysed Direct Growth of Graphene Epitaxial Layer on SiC Substrates By Chemical Vapor Deposition
Authors: Jeganathan Kulandaivel , Dharmaraj Periyanagounder 
Published: February 2020

Graphene, fascinates with its relativistic linear dispersion relation at low energies and the chiral nature of charge carriers, has garnered tremendous interest due to its unusual properties including high electron mobility with low electronic scattering which makes it as a potential candidate in nanoelectronics and photonic devices. Several outstanding advancements in graphene fabrication technology have been explored including research grade mechanical exfoliation of graphite, chemical vapor deposition (CVD), and thermal decomposition of SiC and chemical methods. In particular, the thermal decomposition of SiC surfaces is presently being a very promising approach since it offers wafer scale growth of graphene layers and a promise for high speed nanoelectronics devices. This method utilizes thermal energy to sublimate the topmost Si atoms from the SiC and carbon atoms bond together to form epitaxial graphene.
At present, ever growing effort is centered on the direct growth of graphene on SiC substrates by external carbon feedstock using CVD as it would offer several benefits toward the development of wafer scale industrial production of graphene technology on SiC. Moreover, this method facilitates the controlled monolayer growth on the flat SiC surface with high mobility and desirable band gap by varying the mass transport of the carbon precursor. However, a catalytic material must entail to soluble the decomposed carbon atoms on SiC surface to form carbon layers since the underlying SiC shown to have very weak catalytic activity. In this work, we employ a novel approach by utilizing metal gallium vapors as a catalyst and exposing it onto the SiC substrates along the carbon precursor to promote the catalytic activity for the direct fabrication of graphene. At elevated temperatures on the SiC surface, the gallium vapors assist to decompose the acetylene gases and nucleate the carbon atoms to form graphene layers over the substrate scale. The growth mechanism of epitaxial graphene on SiC substrate and the results will be presented in detail.
References:

P. Dharmaraj et al, J. Phys. Chem. C, 117, 19195 (2013)

P. Dharmaraj et al, Appl. Phys. Lett. 108, 051605 (2016).

K. Murakami et al, Appl. Phys. Lett.106, 093112 (2015).

W. Strupinski et al, Nano Lett. 11, 1786 (2011).
Development of Low-Temperature Methane Gas Sensors By Using Cup-Stacked Carbon Nanofilament-Supported Pd Catalyst
Authors: Koyama Kenta , Oda Hirokazu , Nakagawa Kiyoharu , Ando Toshihiro 
Published: February 2020

Methane gas is found in environment, industrial and domestic areas. On the other hand, methane can cause explosions due to its inflammability. Thus, detection of methane gas in the environment is very important to avoid any accidental explosion. Catalytic combustion-type methane gas sensors can detect methane gas immediately. This type of methane gas sensors utilizes heat from catalytic combustion of methane by Pd-loaded catalysts. To indicate high catalytic activity, it is necessary for catalyst to heat around 250 ~ 600 °C because of thermochemical stability of methane. Consequently, electrical power consumption on the sensors is large. Hence development of efficient methane sensors that could work even at low temperatures is required.
In this work, cup-stacked carbon nanofilament (CSCNF) was used for Pd support material. γ-Al2O3 was used for general catalytic combustion-type methane gas sensors. Relatively large amount of Pd is required to indicate catalytic activity in using γ-Al2O3 support. On the other hand, CSCNF has functional groups such as C=O carbonyl-type structures and C-O-C ether-type structures on its edge surface regularly. These functional groups interact with metallic ion in preparing catalysts by impregnating method. Therefore, Pd can be discretely distributed in small particles on the surface of CSCNF. CSCNF supported catalysts are considered to indicated high activity with even small amount of Pd. Therefore, low-temperature combustion of methane is expected. Moreover, sensors can detect heat of methane combustion immediately because CSCNF has good thermal conductivity.
Catalytic activity of Pd/CSCNF was evaluated by temperature programmed reaction (TPR). This catalyst combusted 1 % methane in air at relatively low temperature 270 °C. Pd/γ-Al2O3, which was reference, combusted methane at 330 °C. CSCNF support was able to upgrade catalytic activity of Pd nanoparticles. Pd/CSCNF could reduce methane combustion temperature 60 °C lower than that of Pd/γ-Al2O3. It seems that CSCNF supported catalysts are attractive for methane combustion at low temperatures. CSCNF-loaded catalysts are more efficient for catalytic combustion-type methane gas sensors than the conventional sensors.
The Redox Reaction of Triiodide Ions/Iodide at Various Carbon Nanohorn Films-Modified Electrodes Prepared By the Electrophoretic Deposition Will be Discussed
Authors: Matsunaga Mariko , Suda Kento 
Published: February 2020

Various types of nano carbon film-modified electrodes have been investigated for the application to a catalyst or catalyst support as an alternative to platinum electrodes because of their large specific surface area, high porosity, excellent electron conductivity, and the relative chemical stability. However, in our recent studies, the peeling resistance of these electrodes in solutions was confirmed to be weak in many cases. Then, we developed an electrophoretic deposition method to increase the pealing resistance using silane coupling agents(1). As a result, a film is successfully deposited homogeneously on the entire transparent electrodes (Figure) with strong pealing resistance against an acidic solution, even with nanohorns, which is known to show high water solubility. In addition, the film thickness is demonstrated to be controllable by the deposition time and voltage. The redox reaction of triiodide ions/iodide couples are confirmed to take place at these electrodes depending on the thickness of the film. The redox reaction of triiodide ions/iodide couple at various carbon nanohorn films-modified electrodes prepared by the electrophoretic deposition will be discussed on the day.
(1) “Preparation of Carbon Nanohorn Films by Electrophoretic Deposition with Silane Molecules for Application to Counter Electrodes of Dye-Sensitized Solar Cell,” Kento Suda, Rikiya Karasuno, Mariko Matsunaga, The 83th Annual Meeting of Japan Electrochemical Society, Osaka, Japan, Mar. (2016).

Figure 1