bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Transferred Graphene Based Solar Cell
Authors: Shin Junsung , Kwon Younghwi , Seo Yongho 
Published: February 2020

Graphene is a two-dimensional material which is flexible and has a high conductivity. We grow a single layer graphene through chemical vapor deposition (CVD). Graphene which is grown by CVD has single layer and large specific surface area about 2620 m2/g, theoretically. Among the properties of graphene, high electrical conductivity and transparency are important advantages as an emerging material of solar cell. Using Schottky barrier at the interface between graphene and Si, solar cells have been developed. In order to enhance the solar cell efficiency, IV characteristics of the Schottky junction have been studied.
We use CVD graphene grown on copper foil and silicon wafer (n-doped <100>, 1-10 Ohm·cm, 300 nm oxide, LG Siltron). First, (5x5 mm2) window pattern is exposed on silicon through photolithography. The oxygen layer of the patterned area is removed using BOE (7:1 water:HF) for 4 minutes. The photoresist is removed in acetone at least 10h. A square shape electrode with Ti (10 nm)/Au (90 nm) is deposited on silicon oxide. Ag (300 nm) is deposited on backside of silicon and annealed to have an Ohmic contact. After all these processes are finished, graphene was transferred. Doping on graphene is one way to increase the efficiency of Schottky junction solar cell. We compare none-doped graphene with chemically doped graphene by HNO3 and bis (trifluoromethanesulfonyl) amide. This could be an alternative for the cheap and environmentally friendly solar cell in the future.
Electrodeposition and Characterization of Thin Film of Black-Gold
Authors: Piciollo Emanuele , Picchi Claudio , Ceccarini Alessio , Salvietti Emanuele , De Luca Antonio , Di Benedetto Francesco , Caporali Stefano , Innocenti Massimo 
Published: February 2020

White gold and yellow gold are the most common types of gold colours used in jewellery making. Anyway lots of other colours of gold are also possible to achieve by electroplating and some of these colours may surprise. At the moment the market is gaining more and more interesting in purple gold, or black gold and even blue gold.
There are two electrochemical deposition processes used to obtain such colours: the first one is by formation of special gold metal compounds also referred to as Intermetallic Compounds. The second process is by forming a surface coating on gold, also referred to as Patination of Gold.
Here we present some methods to prepare Black gold thin films.
Amorphous carbon is used at times during Plasma Assisted Chemical Vapour Deposition process. Controlled oxidation of carat gold containing chromium or cobalt can also be used to yield black gold.
We investigate mainly thin films obtained by Electrodeposition processes.
Electrodeposition using black Rhodium or Ruthenium added to gold electroplating solution is one way. Electroplating solutions containing Ruthenium give a slightly harder black coating as compared to electroplating solutions containing Rhodium. We present some electrochemical results about the formation of thin films of black gold and their morphological characterizations by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM).
We’re going also to evaluate a correlation between films electrodeposited from different plating baths and corrosion resistance of the films themselves.
Electrochemical Behavior of Silver Electrodeposition Using Gel Electrolyte
Authors: Sato Haruto , Hoshi Yoshinao , Shitanda Isao , Itagaki Masayuki , Tagaya Michiko 
Published: February 2020

Partial plating method is often applied to the fabrication of the printed wiring board by using silk-screen printing. However, the complex preprocessing and post-processing for mask pattern formation and removal are necessary in this method. In addition, a large amount of plating solution is required in the plating tank in which the substrate for electrodeposition is immersed. In order to solve these problems, Itagaki et al. 1, 2) applied the gel electrolyte as the electrolyte solution for the partial plating of copper and nickel. In this case, a little plating solution was only used for the partial plating without masking process.
On the basis of the partial plating method using the gel electrolyte reported by Itagaki et al. 1), the partial plating of silver was performed in the present study. A three-electrode cell was used for the electrochemical measurement. The working electrode was the copper plate whose surface was covered with the gel electrolyte containing the silver ions. In this case, the preprocessing of copper plate was performed to remove the oxide film formed on the copper surface in the air. The counter electrode was a platinum wire. The reference electrode was a KCl-saturated silver/silver chloride electrode (SSE). The electrolyte solution was gellan gum solution containing KOH (pH=7), which was prepared from reagent grade chemicals and distilled water. All measurements were carried out by a potentiostat (Hokuto Denko, HZ-7000).
The partial plating of silver was performed by a galvanostatic polarization to determine the suitable condition of electrodeposition. In addition, the potentistatic polarization measurement was carried out for investigation of electrodeposition behavior.
Reference
[1] M. Itagaki, K. Shimoda, K. Watanabe, K. Yasuda, J. Surf. Finish. Soc. Jpn., 54, 41 (2003).
[2] M. Itagaki, I. Shitanda, W. Nakamura, K. Watanabe, Electrochim. Acta, 52, 6421 (2007).
The Critical Role of Supporting Electrolyte Selection on Flow Battery Cost
Authors: Perry Mike L. , Milshtein Jarrod David , Darling Robert M. , Drake Javit A , Brushett Fikile R. 
Published: February 2020

Redox flow batteries (RFBs) are promising electrochemical devices for grid-scale energy storage due to their many favorable inherent attributes, such as decoupled power and energy ratings, as well as excellent performance and capacity retention. Recently, significant improvements in cell performance have made RFB systems more viable than ever. However, to meet the U.S. Department of Energy long range capital-cost target of $150 kWh-1, additional cost reductions are needed. One promising route is new active species for RFBs designed for lower cost or improved performance. These next-generation RFB chemistries are likely to be engineered molecules or complexes, such as redox-active organic or organometallic compounds, which offer a multitude of possibilities. A key consideration in the selection of any new RFB chemistry is the supporting electrolyte, which has a significant influence on the membrane resistance, electrolyte conductivity, and electrolyte viscosity. All of these physical parameters have a major impact on RFB performance and cost. Therefore, it is useful to quantify changes in economic viability for various RFB chemistry options with different aqueous supporting electrolytes paired with different types of membranes, which is the focus of this work. A techno-economic model is used to estimate RFB-system costs for the different membrane and supporting electrolyte options considered herein. Variations in cell performance due to the working ion selection and electrolyte viscosity can yield battery cost differences in the $100’s kWh-1, and this analysis allows for quantification of cost performance changes by selecting certain electrolyte characteristics. Beyond the conventional RFB design incorporating small active species and an ion-exchange membrane (IEM), this work also considers size-selective separators (SSS) as a cost-effective alternative to IEMs. The SSS concept utilizes nano-porous materials with no functionalization for ion selectivity, and active species that are too large to pass through the pores. Across the entire design space, SSS separators with low viscosity electrolytes offer the lowest RFB costs. Acknowledgements
This work was supported by the Joint Center for Energy Storage Research (JCESR), an Energy Innovation Hub funded by the United States Department of Energy. J.D.M. acknowledges additional financial support from the National Science Foundation Graduate Research Fellowship Program.
Electrodeposition of NiPd Alloy in Alkaline Ni2+ – Pd2+ – Cl– – NH3 – H2O System
Authors: Mech Krzysztof , Chopart Jean Paul , Wrobel Miroslaw , Zabinski Piotr , Szacilowski Konrad 
Published: February 2020

Synthesis of NiPd alloy is investigated in many research centers in the world mainly due to its interesting properties making possible its application as magnetic and catalytic materials. NiPd alloys were investigated also as catalysts in autothermal reforming of methane (1), counter electrode electrocatalyst in liquid-junction solar cells (2), utilization of CO2 and methane in dry reforming process (3), anodes in methanol oxidation (4) and toluene hydrogenation (5). Exchange current density versus the enthalpy of hydrogen adsorption (Log(i0)-dGMe-H) dependence allows on assumption that material composed of Ni and Pd will exhibit high catalytic properties towards hydrogen evolution reaction (HER). Previously we reported studies on electrochemical co-deposition of nickel with palladium from acidic solutions containing aquachloro- complexes of both elements (6) as well as palladium with cobalt (7, 8) and nickel with molybdenum (9). In literature, in spite of its wide application range, few reports exist concerning electrodeposition of NiPd alloys. Existing reports are focused on synthesis of NiPd alloys from suplphate-chloride (5), ethylenediamine (4) and chloride (6) based baths. In present work authors reported studies focused on electrochemical deposition in alkaline ammonia based system for first time.
Described studies were started from thermodynamic and UV-Vis analysis enabling qualitative description of analysed system. Electrochemistry of Ni2+ – Pd2+ – Cl– – NH3 – H2O system was analyzed based on results of cyclic voltammetry combined with electrochemical quartz crystal microbalance (EQCM). In further step synthesized alloys were characterized towards their compositions (WD-XRF), morphology (SEM, AFM), structure (XRD) and catalytic properties towards HER.
References
1. I. Z. Ismagilov, et al., International Journal of Hydrogen Energy(2014).
2. P. Yang, C. Ma and Q. Tang, Electrochimica Acta, 184, 226 (2015).
3. B. Steinhauer, et al., Applied Catalysis A: General, 366, 333 (2009).
4. K. S. Kumar, et al., Surface and Coatings Technology, 202, 1764 (2008).
5. K. Chen, et al., Chinese Journal of Catalysis, 17, 352 (1996).
6. K. Mech, et al., Applied Surface Science(2016).
7. K. Mech, et al., J Appl Electrochem, 44, 97 (2014).
8. K. Mech, et al., Electrochimica Acta, 104, 468 (2013).
9. K. Mech, et al., Archives of Metallurgy and Materials, 58, 227 (2013).
Impedance-Based Characterization of Raw Materials Used in Electrochemical Manufacturing
Authors: Orazem Mark E , Riemer Douglas P. 
Published: February 2020

The impedance-based screening of raw materials has a tremendous positive impact in an industry where the state of the oxide film on stainless steel strongly influences process and product performance. This application was made possible by the significant progress made in the understanding of impedance data obtained on stainless steels. Huang et al. [1,2] have demonstrated that, for a disk electrode, frequency dispersion can be avoided by reducing the size of the electrode. Alexander et al. [3] have shown that frequency dispersion associated with specific geometries or distributions can be correlated by use of a characteristic dimension. The frequency at which the impedance response is corrupted by time-constant dispersion is inversely related to the characteristic dimension. This work facilitates selection of proper electrode design.
Even at frequencies below that at which specific geometries or distributions cause distortions to the impedance response, constant-phase-element (CPE) behavior can be seen which is attributed to properties of oxides on steel. Hirshorn et al. [4,5] have identified an approach through which CPE parameters may be interpreted in terms of oxide film thickness and dielectric constant. Orazem et al. [6] described application to different types of steel and to human skin. Riemer and Orazem [7] have described how this improved understanding of the origin of frequency dispersion has given rise to industrial application of impedance spectroscopy to provide rapid, inexpensive, and accurate measurement of the oxide film thickness.
Understanding what parts of the impedance spectra are truly useful requires an inherent understanding of the fundamental mathematics, and leads to the ability to make accurate and rapid measurements of oxide film thickness by EIS. Riemer and Orazem [7] stated that “This ability is invaluable from a manufacturing perspective as it serves as a method to screen the incoming raw material, as well as the product in-between different steps in the manufacturing process, allowing for greatly enhanced quality control.”
References

V. Huang, V. Vivier, M. E. Orazem, N. Pébère, and B. Tribollet, Journal of The Electrochemical Society, 154 (2007), C81-C88.

V. Huang, V. Vivier, M. E. Orazem, I. Frateur, and B. Tribollet, Journal of The Electrochemical Society, 154 (2007), C89-C98.

C. L. Alexander, B. Tribollet, and M. E. Orazem, Electrochimica Acta, 201 (2016), 374-379.

B. Hirschorn, M. E. Orazem, B. Tribollet, V. Vivier, I. Frateur, and M. Musiani, Journal of The Electrochemical Society, 157 (2010) C452-C457.

B. Hirschorn, M. E. Orazem, B. Tribollet, V. Vivier, I. Frateur, and M. Musiani, Journal of The Electrochemical Society, 157 (2010) C458-C463.

M. E. Orazem, B. Tribollet, V. Vivier, S. Marcelin, N. Pébère, A. L. Bunge, E. A. White, D. P. Riemer, I. Frateur, and M. Musiani, Journal of The Electrochemical Society, 160 (2013), C215-C225.

D. P. Riemer and M. E. Orazem, The Electrochemical Society Interface, Fall 2014, 23:3 (2014), 63-67.
Electrodeposition of Al from Dimethyl Sulfone-Aluminum Chloride Baths Under Dry Air
Authors: Miyake Masao , Okamoto Hiroaki , Hirata Mizuki , Hirato Tetsuji 
Published: February 2020

Electrodeposition of Al requires the use of a non-aqueous bath, and it is usually carried out under an inert gas atmosphere such as nitrogen and argon using a glove box to protect the bath from absorbing moisture. However, the operation of the electrodeposition process under such conditions reduces the producibility and increases the cost, hindering its industrialization. If Al electrodeposition can be carried out in dry air, it would facilitate the operation and drastically lower the process cost. In this study, we examine the feasibility of the electrodeposition of Al under dry air using an organic bath, dimethylsulfone (DMSO2)-AlCl3 system (1-6).
The electrodeposition of Al was carried out at 110°C under dry air with a dew point of ~−60°C in a dry chamber. The electrodeposition was also carried out under Ar atmosphere using a glove box, and the deposits obtained under the two atmospheres were compared.
Cyclic voltammetry and XRD analysis of the deposits confirmed that the Al metal can be electrodeposited from the DMSO2-AlCl3 bath even in dry air. However, the Al film obtained in dry air tended to have black spots and a rough surface with scratch-like non-deposited portions. In contrast, a uniform, flat, silver-white Al film covering entirely the surface of the substrate is electrodeposited in Ar atmosphere under the same conditions, except for the atmosphere. This poor appearance of the Al film electrodeposited in dry air could be resolved by adding an additive to the bath. The current efficiency for the Al electrodeposition was slightly lower in dry air than that in Ar atmosphere, but it was still higher than 90%.
References
1. T. Hirato, J. Fransaer and J. P. Celis, J Electrochem Soc, 148, C280 (2001).
2. S. Shiomi, M. Miyake and T. Hirato, J Electrochem Soc, 159, D225 (2012).
3. M. Miyake, S. Tajikara and T. Hirato, Surf Coat Tech, 205, 5141 (2011).
4. M. Miyake, H. Motonami, S. Shiomi and T. Hirato, Surf Coat Tech, 206, 4225 (2012).
5. M. Miyake, Y. Kubo and T. Hirato, Electrochim Acta, 120, 423 (2014).
6. M. Miyake, H. Fujii and T. Hirato, Surf Coat Tech, 277, 160 (2015).
The Mechanism of Impedance Increase in Nickel-Rich NMC Cathodes
Authors: Lee Rung-Chuan , Tian Chixia , Doeff Marca , Kostecki Robert 
Published: February 2020

The electrochemical performance of nickel-rich NMC cathode materials in Li-ion batteries depends on the kinetic control of side reactions at NMC-electrolyte/interface such as electrolyte oxidation, surface film formation, surface structure transformation and transition metal dissolution. However, the exact mechanism i.e. interdependence, sequence and impact of these interfacial phenomena is still poorly understood. The effect of surface reconstruction from layered- to spinel- or rock salt-phase(1, 2) in NMC materials during cycling on the kinetics of charge/discharge process remains unclear. As much as the exact chemical and physical properties of such surface reconstruction layer are still largely unknown, it is likely that it occurs simultaneously with other surface reactions and phenomena, which all together are difficult to deconvolute and evaluate.
To understand the mechanism of the surface reconstruction layer formation in Ni-rich NMC material during battery storage and its possible effect on the electrode and cell impedance a surface modification was deliberately induced in NMC particles artificially a priori via exposure to the electrolyte at elevated temperatures. The reaction of the electrolyte with NMC powders and the phase reconstruction of NMC surface were probed by surface sensitive techniques, including Raman, IR, SEM and X-ray absorption spectroscopy in total electron yield mode (XAS-TEY). Accompanying electrochemical testing including electrochemical impedance spectroscopy (EIS) was performed with half-cell configuration coin cells. Through comparison of the surface chemical properties and electrochemical performance between pristine NMC and treated samples, we were able to demonstrate that this artificial reconstruction layer on NMC does not cause a critical resistance in the battery. The treatment was shown to demonstrate some positive effects on the performance: i) higher capacity retention and ii)less resistance growth during electrochemical cycling. Surface chemical analysis shows that treated electrodes had reduced amount of organic film formation and less subsequent growth of reconstruction layers during electrochemical cycling compared with pristine NMC, indicating that an artificial reconstruction layer might suppress other degradation process of the battery, such as film formation and metal dissolution.

Acknowledgement

This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

Reference

1. F. Lin, I. M. Markus, D. Nordlund, T. C. Weng, M. D. Asta, H. L. L. Xin and M. M. Doeff, Nat Commun, 5(2014).
2. S. K. Jung, H. Gwon, J. Hong, K. Y. Park, D. H. Seo, H. Kim, J. Hyun, W. Yang and K. Kang, Adv Energy Mater, 4 (2014).
(Invited) Unveiling Irreversible Side-Reactions in Li-Ion Batteries with Online Electrochemical Mass Spectrometry
Authors: Bolli Christoph , Guéguen Aurélie , Berg Erik J. 
Published: February 2020

Li-ion batteries will dominate the high-end rechargeable energy storage market for a foreseeable future. Current research and development of commercially relevant electrode/electrolyte systems focus strongly on extending the lifetime of the cells. Progress is however impeded by the lack of fundamental understanding of the underlying lifetime-limiting processes. Online Electrochemical Mass Spectrometry (OEMS) provides unique means for mechanistic studies of such adverse processes by enabling an operando monitoring of the onset, rate and extent of side-reactions with unparalleled sensitivity and selectivity.
Decomposition reactions involving (1) the electrode active material, (2) conductive carbon and (3) binder, as well as (4) the electrolyte solvent, (5) salt, along with (6) eventual additives, will be discussed. The Ni-rich layered mixed transition metal oxides (LiNixCoyMnzO2) are currently the best performing Li-ion cathode materials on the market. Surface phase transformations during the initial cycles however lead to composition- and potential-dependent evolution of O2, which is shown to be strongly related to the Ni-content of the oxides.1 Decomposition of electrode-processing-related residues and of electrolyte solvents leads to evolution of CO2, particularly in the first cycles, and initiates further chemical reactions with electrolyte salt (e.g. observed as HF and POF3).2 Electrolyte additives (e.g. vinylene carbonate, silyl-phosphates, etc.) can however suppress these side-reactions, e.g. by scavenging intermediate side-products and OEMS provides further verification of their reaction mechanism. In addition, electrolyte additives may also be exploited as chemical probes enabling operando monitoring of the degradation of other cell components, such as for example the electrode binder.3

References

D. Streich, C. Erk, A. Guéguen, P. Müller, F. Chesneau, E. J. Berg, Submitted.

A. Guéguen, D. Streich, M. He, M. Mendez, F. F. Chesneau, P. Novák, E. J. Berg, J. Electrochem. Soc. 163 A1095-A1100 (2016).

A. Guéguen, C. Bolli, M. Mendez, F. F. Chesneau, E. J. Berg, Submitted.
Dynamic Chemical X-Ray Microscopy on Energy Storage Materials
Authors: Weker Johanna Nelson , Wise Anna M , Li Yiyang , Ruther Rose Emily , Chueh William C , Nanda Jagjit , Toney Michael F 
Published: February 2020

The shift from fossil fuels toward clean, renewable energy will require significant improvements in rechargeable battery technology for electric vehicles. Current battery technology limits electric vehicles to a short travel range, slow recharge, and costly price tag. Li-ion batteries promise the high specific capacity required to replace the internal combustion engine with a number of possible earth abundant electrode materials; however, setbacks such as capacity fading hinder the full capability of these rechargeable batteries. In the search for better electrode materials, high resolution chemical imaging during typical battery operation is vital in understand and overcoming the failure mechanisms of these materials.
By combining X-ray absorption spectroscopy with high resolution, hard X-ray transmission microscopy (TXM), we have tracked the chemical changes of electrode material in real time during typical battery operation (Figure). [1, 2] We will discuss recent results tracking electrochemical and morphological changes in cathode materials during cycling, including LiFePO4,[3] LiCoO2, and Li2Cu0.5Ni0.5O2. Finally, we will discuss how ptychography, an emerging X-ray microscopy technique that promises sub-5 nm resolution, has the potential to image batteries during cycling at resolutions that rival in situ TEM with liquid cells.
[1] J.N. Weker, X. Huang, M.F. Toney, 2 (2016) 14-21.
[2] J. Nelson Weker, M.F. Toney, Advanced Functional Materials, 25 (2015) 1622-1637.
[3] J. Nelson Weker, Y. Li, R. Shanmugam, W. Lai, W.C. Chueh, ChemElectroChem, 2 (2015) 1576-1581.

Figure 1