bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Power-to-Value: Metal Foam Catalysts for the Electrochemical Conversion of CO2
Authors: Dutta Abhijit , Rahaman Motiar , Kiran Kiran , Zelocualtecatl Montiel Ivan , Cedeño López Alena , Moreno-García Pavel , Broekmann Peter 
Published: December 2020

The electrochemical conversion of CO2 (denoted as CO2RR) has attained significant interest in the catalysis research worldwide over the recent years as it provides means of transforming an environmentally harmful molecule back into products of higher value (e.g. high energy density fuels, chemical feedstock and useful commodity chemicals such as carbon monoxide). This process becomes particularly sustainable when using the surplus of electric power produced from renewable hydro, wind or solar sources (power-to-value concept). Substantial progresses have already been made during the last decade in the tailored design of novel catalyst materials needed to increase the energy efficiency of the CO2/water co-electrolysis and to guide the product distribution reaction into the desired direction. These progresses remained, however, restricted to the fundamental research whereas no technologically and economically feasible process could be established on an industrial scale so far. One key challenge left is related to the particular stability of the catalyst materials, a crucial pre-requisite for any industrial application of catalytic processes.
In this contribution, concepts for the design of monometallic and bimetallic CO2RR catalysts will be discussed that are based on the additive-assisted electroplating of high-surface area metal foams. Main target products of the CO2RR addressed herein are formate (Bi foams), syngas (Ag foams; see Figure below) as valuable chemical feedstock for a subsequent non-electrochemical conversion process (Fischer-Tropsch, Rheticus process/Siemens-Evonik), and high energy density fuels (e.g. ethanol, n-propanol; bimetallic AgCu foams and co-alloed PdCu foams). Advanced operando Raman spectroscopy will be demonstrated to be highly useful for the identification of active catalyst species under CO2 electrolysis conditions.

Figure 1
Controllable Electrodeposition of Co-Ni-S on Carbon Paper for Electrocatalytic Hydrogen Evolution Reaction
Authors: Guo Wen Wu , Ahn Sang Hyun 
Published: December 2020

Development of highly active catalyst for hydrogen evolution reaction (HER) is an urgent research to realize the energy consumption transformation from fossil flue to clean and renewable hydrogen energy and alleviate the energy crisis and. Electrochemical water splitting offers an ideal approach for hydrogen production with ultrahigh purity, which need a cost-effective electrocatalyst to drive the HER. Until now, Pt-group metals have been proved to be the best electrocatalysts for HER due to the extraordinary low overpotential near the thermodynamic potential of HER, but their widespread commercial application on a large scale is hampered by the prohibitive cost and scarcity.
In this study, we reported amorphous Co-Ni-S catalysts fabricated on carbon paper by a simple one-step electrodeposition. By varying the deposition potential/time and concentration of sulfur source, the morphologies and compositions of Co-Ni-S were controlled, and optimal condition for synthesis was obtained. The structure, surface morphology and composition of deposits were characterized in detail. And the electrochemical performance and stability of catalysts were tested in alkaline media by directly using the as obtained Co-Ni-S/Carbon Paper as a cathode. The characterization results showed Co-Ni-S was amorphous and uniformly deposited on carbon paper. And the electrochemical test indicated that Co-Ni-S/Carbon Paper has acceptable performance with low overpotentials of 99mV at 10mA/cm2, Tafel slop of 85mV/dec and long-tern durability. Moreover, the double-layer capacitance (Cdl) result indicated that Ni−Co−S catalyst possesses high electrochemical surface area (ECSA), which could provide abundant active sites for electrocatalytic reaction
Ultrathin RF-Sputtered Lipon Layers for Conformal Lithium Deposition
Authors: Wodarz Siggi , Kee Yongho , Cotte Stéphane , Mees Maarten , Barde Fanny , Vereecken Philippe M. 
Published: December 2020

The transformation from liquid-based Li-ion batteries to solid-state Li-metal batteries is a necessary step to achieve beyond energy densities of 1000 Wh/L. However, the commercial widespread application of the solid-state Li-metal batteries has been hindered by several electrolyte constraints, among which narrow electrochemical window and low compatibility against metallic lithium as negative electrode. Among the various solid-state electrolytes, nitrogen doped lithium phosphate glass or LiPON is a well-known material with an excellent electrochemical stability above 5 V and a good compatibility against metallic lithium [1]. However, owing to its low ionic conductivity (~10-6 S/cm), application of LiPON is limited for thin-film batteries in medical implants and various sensor systems. For thin-film batteries, because the path length for Li+ ion diffusion is in the order of few 100 nm or less, low conductivity of LiPON is enough for application. LiPON has also been evaluated as solid-electrolyte coatings on electrode particles as buffer layer between active material and the bulk electrolyte. In a thin-film stack, it is an ideal model system for electrochemical study.
Previously, we investigated detailed electrochemistry of RF-sputtered LiPON thin films with different thickness [2]. We demonstrated formation of an electronically insulating LiPON films down to 15 nm with a maximum conductivity of 1×10-6 S/cm. We have also formulated a breakdown mechanism for LiPON layer based on experimental measurements and thermodynamic considerations. In the present work, we investigated LiPON thin-films as artificial solid-electrolyte interphase for lithium plating and stripping on copper current collectors. The stability of 100 nm down to 10 nm LiPON thin-films was evaluated by electrochemical galvanostatic cycling test of Li plating/stripping with carbonate-based electrolyte. The LiPON thin-film with 100 nm showed reversible plating/stripping of Li with an overpotential of only ~40 mV for current density of 0.1 mA/cm2 for over 100 cycles, indicating formation of a uniform Li layer in-between substrate and LiPON without breaking of LiPON layer during the cycles. Furthermore, even with the thickness of only 10 nm, LiPON thin-film demonstrated significant improvement of coulombic efficiency of Li plating/stripping compared to without LiPON layer. In the presentation, thickness-dependence of LiPON on growth behavior of Li will be further discussed.

Reference

[1] X. Yu, J. B. Bates, G. E. Jellison, Jr., and F. X. Hart, J. Electrochem. Soc., 144 (1997) 524-532.
[2] B. Put; P.M. Vereecken; J. Meersschaut; A. Sepúlveda; A. Stesmans, ACS Appl. Mater. Interfaces., 8 (2016) 7060-7069.
Novel One-Step Electrophoretic Deposition of Membrane-Electrode Assembly for Flexible Batteries Application
Authors: Golodnitsky Diana , Cohen Elazar , Lifshitz Moran , Gladkikh Alexander , Kamir Yosef , Ben Barak Ido 
Published: December 2020

The focus on shifting towards miniaturized products coupled with the booming demand for consumer electronics are some of the key-driving factors behind the flexible-battery market. In the development of innovative power sources, freeing from design limitation along with the synthesis of reliable electrochemical materials with well-tuned features, is considered to be the most important technical prerequisite.
In the current research we present for the first time, a unique, single-step method for the preparation of a membrane-electrode assembly for flexible-batteries application. Concurrent electrophoretic deposition (EPD) of positive and negative battery electrodes (LFP and LTO) on opposite sides of a commercial nanoporous membrane (Celgard 2325) results in the formation of a three-layer-battery structure. The cell comprising this electrophoretically deposited structure ran for more than 150 cycles with 125-140mAh/g capacity, which approaches the theoretical value of lithium iron phosphate. The electrodes can be deposited either cathodically or anodically by replacing the interchangeable charging agents, like polyethyleneimine and polyacrylic acid. These polyelectrolytes, when adsorbed on the particles of the active material, serve also as the binders. The simultaneous EPD, which we developed, can be used for the simple and low-cost manufacturing of a variety of cathode and anode materials on nanoporous polymer- and ceramic ion-conducting membranes for energy storage devices
Silicon-Graphite Anode with High-Areal Capacity for Li-Ion Battery
Authors: Li Peng , Han Geumjae , Sun Yang-Kook 
Published: December 2020

Nowadays, researchers are increasingly interested in silicon active material for lithium-ion batteries, which could meet the ever-increasing demand for high energy density owing to their satisfactory theoretical capacity (~4200 mAh g-1). Nevertheless, replacing the commercial graphite totally with silicon is still insurmountable due to bottlenecks such as low loading level and unsatisfactory areal capacity. Therefore, in this work, we turned eyes back on improved graphite anode with modified silicon cooperation through a facile blending process. The nano/microporous silicon active mateiral with boron doping and carbon nanotube wedging (B-Si/CNT) exhibits stable electrochemical performance (88.2% retention after 200 cycles at 2000 mA g-1) and high reversible capacity (ca. 2400 mAh g-1). After graphite cooperation, the resultant B-Si/CNT-graphite composite could illustrate an areal capacity of 5.2 mAh cm-2 with a high mass loading (11.2 mg cm-2). Besides, the enhanced anode also demonstrates acceptable utilization in lithium ion full battery with 2 mol% Al-doped full concentration gradient Li[Ni0.76Co0.09Mn0.15]O2 as cathode, showing a good energy density of ca. 8.0 mWh cm-2. Furthermore, considering that low initial coulombic efficiency (ICE) of silicon is another drawback for its industrial application, tough graphite framework and optimized lithium polyacrylate binder could be applied to increase the ICE effectively.

Reference
s

1. U.-H. Kim, S.-T. Myung, C. S. Yoon and Y.-K. Sun, ACS Energy Lett.
2017,
2, 196.
2. J. H. Lee, C. S. Yoon, J.-Y. Hwang, S.-J. Kim, F. Maglia, P. Lamp, S.-T. Myung and Y.-K. Sun, Energy Environ. Sci., 2016,
9, 2152.
3. P. Li, J.-Y. Hwang and Y.-K. Sun, ACS Nano,
2019,
13, 2624.

Figure 1
Molecularly Imprinted Polymer for Selective Electrosynthesis of Biphenols
Authors: Sudagar Alcina Johnson , Borowicz Pawel , Asztemborska Monika , Kutner Wlodzimierz , Noworyta Krzysztof R. 
Published: December 2020

Molecularly imprinted polymers (MIPs) have been widely studied for sensing and separation of compounds selectively. These artificial biomimicking recognition units are highly sensitive and selective to target analytes. Electrochemical preparation of MIPs offers advantages including ease of preparation as well as control over the polymer nucleation and growth, thickness, and film morphology. Moreover, it is possible to follow the formation of cavities electrochemically through the gate effect. Few reports have focussed on selective catalysis by using MIPs. However, the application of these MIPs in the field of electrocatalysis remains unexplored and, therefore, there is a large research scope in this domain.
Biphenols are structural motifs of several molecules in nature and for many drugs. They are efficient ligands for catalytic systems and are highly stable under electrochemical condition. In particular, 3,3,5,5-tetramethyl-2,2-biphenol acts as a significant backbone in phosphorus-based ligand systems for calatysis. The oxidation of 2,4-dimethylphenol yields several different products including polycyclic compounds formed by C-H bond activation (Scheme 1). Therefore, designing a scalable process, in which the desired biphenol is selectively produced, is challenging.
In the present work, we aim to develop MIPs that can be applied for selective electrosynthesis of the desired C-C coupled biphenol through electro-oxidation of the corresponding phenol. For this purpose, the functional monomer was selected based on the Gibbs free energy of its interaction with the target biphenol template in density functional theory (DFT) simulations. Complexation of the functional monomer with the template was confirmed by spectroscopic titrations. Electroactive monomers can polymerize to form either conducting or nonconducting polymers. In our system, a conductive MIP film was prepared using derivatized thiophene functional monomers. Then, the template extraction process was optimized. Electro-oxidation of 2,4-dimethyl phenol was studied in detail to reach as high yield as possible of the desired biphenol product at a bare platinum electrode. HPLC-MS was used to identify the substrate and products of the electrosynthesis. Then, selectivity of the electrosynthesis study was performed for the MIP film-coated electrode in comparison to a non-imprinted polymer (NIP) film-coated electrode, and a bare electrode.

Figure 1
Electrospun Nanofibers for Applications in Energy Harvesting and Generation
Authors: Yu Sooyoun , Chen Qi , Yang Steve , Chen Wilfred , Myung Nosang Vincent 
Published: December 2020

Nanofibers have long been exploited as a versatile, attractive material compared to their bulk counterparts due to their exceptionally high specific surface area and aspect ratio, highly porous structure, and wide range of materials that can be used for synthesis. Such unique properties helped exhibit their potential in a variety of applications in areas of energy, healthcare, and environment. Applications in energy are widely studied especially because of the global need for a source of energy and method of energy production that is alternative to the combustion of fossil fuels, as it presents many environmental drawbacks, which ultimately lead to adverse health effects on humans. To bypass the use of fossil fuels, renewable sources such as wind, hydro, geothermal, and solar energy have been introduced; devices that take advantage of alternative sources of energy such as nanogenerators, fuel cells, and thermoelectric generators have been developed.
In this work, hybrid nanofibers were fabricated with precise control of the working parameters to fine tune their properties for various applications, including piezoelectrics and enzymatic fuel cell electrodes. Pure polyacrylonitrile (PAN) nanofibers were first electrospun based on a series of design of experiments to minimize both the diameter and beading. By correlating the solution, electrospinning, and environmental conditions to the resulting solution and nanofiber properties, it was found that not only physical properties such as electrical conductivity but also electrochemical properties of the nanofibers could be controlled. Physical and electrochemical properties of porous carbonaceous nanofibers derived from PAN, zinc acetate and multi-walled carbon nanotubes were studied with SEM, 4-point probe measurement, CV, LSV, and EIS. Based on the electroanalytical methods, the best nanofiber mats were chosen and used as electrodes to immobilize multienzyme cascade systems, a concept of which was demonstrated with a glucose oxidase-BglA bienzymatic system on a customized DNA scaffold as the anodic biocatalyst.
Microstructure-Tailored Ni-Rich NCA Cathode for Next Electric Vehicles
Authors: Ryu HoonHee , Sun Yang-Kook 
Published: December 2020

Li[NixCoyAl1-x-y]O2 (NCA) cathodes have been adapted for the current fleet of electric vehicles, which still have unsatisfactory performances. To further increase the driving range, the Ni content in NCA cathodes should be progressively increased so that the energy density of the lithium-ion batteries is increased. However, an inherent trade-off relation between delivered capacity and cycling stability is clearly observed in Ni-rich NCA cathodes: the capacity gain from Ni enrichment is negated by the rapid capacity fading. The most dominant mechanism for the rapid fading is the microcrack formation of the cathode particles.1,2 Microcracks undermine the mechanical integrity of the Ni-rich NCA cathodes and allow the electrolyte to penetrate the particle interior, thus leading to parasitic surface reactions. Although various attempts, such as optimizing transition metal composition, finding effective doping or coating agents, have been proposed to improve the cycling stability of Ni-rich cathodes, these approaches are not a fundamental solution to the formation of microcracks on the particle.
Recent researches provided valuable insights into a way to suppress microcrack formation.3 Because microcracks nucleate from the abrupt lattice contraction caused by the multiple phase transition during the electrochemical reaction, it is necessary to minimize the local strain build-up for particle integrity. Although intrinsic lattice volume changes are unavoidable during electrochemical reactions, the structural integrity of Ni-rich cathodes can be preserved by engineering the microstructure of cathode particles such that the strain distribution is delocalized.4 In this presentation, we propose boron-doped Li[Ni0.878Co0.097Al0.015 B0.01]O2 (B-NCA88) which have obviously different morphologies compared to a typical NCA cathode. To highlight the dramatic microstructure change caused by boron doping, B-NCA88 and typical Li[Ni0.885Co0.1Al0.015]O2 cathodes are extensively investigated by comparing their electrochemical properties, microcracking behavior, and structural stability.

References

G. W. Nam, N.-Y. Park, K.-J. Park, J. Yang, J. Liu, C. S. Yoon and Y.-K. Sun, ACS Energy Lett.
2019, 4, 2995.

K.-J. Park, J.-Y. Hwang, H.-H. Ryu, F. Maglia, S.-J. Kim, P. Lamp, C. S. Yoon and Y.-K. Sun, ACS Energy Lett.
2019, 4, 1394.

H. H. Sun, H.-H Ryu, U.-H. Kim, J. A. Weeks, A. Heller, Y.-K. Sun and C. B. Mullins, ACS Energy Lett.
2020, 5, 1136.

U.-H. Kim, H.-H. Ryu, J.-H. Kim, R. Mücke, P. Kaghazchi, C. S. Yoon and Y.-K. Sun, Adv. Energy Mater.
2017, 2, 1150.
Electrodeposition of AuxAg1-X Alloys from Thiosulfate Solutions
Authors: Vasiljevic Natasa , Cruz-San Martin Vinicius , Sarua Andrei , Cattelan Mattia , Fox Neil A. 
Published: December 2020

Silver (Ag) and gold (Au) are noble metals of particular interest for future plasmonic, and (bio)sensing applications due to their unique coupling with light in the visible range.[1,2] Recent studies suggest that AuxAg1-x alloy nanostructures of different geometry, composition and size can exhibit interesting new optical phenomena.[3,4,5] Therefore developing new environmentally-friendly (cyanide-free) electrodeposition route to fabricate AuxAg1-x alloys is desirable.[6] Thiosulphate-based solutions are less toxic, and this solution was previously studied for pure Au,[7] pure Ag [8] and recently for AuxAg1-x alloys.[6]
In this work, we will present a systematic study of electrodeposition of AuxAg1-x alloys from thiosulphate solutions on Au and indium-tin-oxide (ITO) substrates. Thin-film alloys (20 nm-100 nm thickness on Au on ITO) of different compositions were electrodeposited by variation of Ag+: Au+ ion concentrations in the solution. The structure of the deposited alloys was explored as a function of the electrodeposition potential and film thicknesses by Atomic Force Microscopy (AFM), and Scanning Electron Microscopy (SEM). Chemical composition of the electrodeposited alloys was determined using X-Ray Photoemission Spectroscopy (XPS).
The electrodeposition on the two substrates showed higher Ag content in the films than expected from the solution composition ratios. Comparison of the linear sweep voltammetry for deposition of alloys on Au and ITO show that the potential at which alloys start depositing for ITO is more negative than on Au. Stoichiometry of films varied between Au20Ag80 to Au50Ag50. Diffusion-limited deposition of alloys at lower overpotentials produced smooth, homogenous films on Au substrates; at potentials higher than 1 V vs MSE, hydrogen-evolution reaction assisted non-uniform growth and formation of instabilities at the surface in both substrates. The electrodeposited alloys were characterised by surface composition and structure sensitive UPD processes such as Pb UPD and Cu UPD. The results showed a correlation between the UPD peaks potential shifts and the UPD charge with alloy compositions.

References

[1] W. A. Murray, W. L. Barnes, Adv. Mat.,
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[2] P.K. Jain, X. Huang, I.H. El-Sayed, M.A. El-Sayed, Acc. Chem. Res.,
41 (2008) 1578-1586.
[3] G. Guisbiers, R. Mendoza-Cruz, L. Bazan-Diaz, J. J. Velazquez-Salazar, R. Mendoza-Perez, J. A. Robledo-Torres, J. L. Rodriguez-Lopez, J. M. Montejano-Carrizales, R. L. Whetten, Jose-Yacaman, M. ACS Nano,
10, 1 (2016) 188-198.
[4] C. Gong, M. S. Leite, ACS Photonics,
3, 4 (2016) 507-513.
[5] G. Wang, X. Chen, S. Liu, C. Wong, S. Chu, ACS Nano,
10, 2 (2016) 1788–1794.
[6] D. A. McCurry, M. Kamundi, M. Fayette, F. Wafula, N. Dimitrov, ACS Appl Mater Interfaces,
3, 11 (2011) 4459-4468.
[7] A. M. Sullivan, P. A. Kohl, J. Electrochem.
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[8] V. Vandeputte, A. Hubin, J. Vereecken, Electrochem. Acta,
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The Effect of Leveler in Cu Electroplating Solution on the Bump Reliability of Flip Chip Packaging
Authors: Jo Yugeun , Lee Woon-Young , Lee Dong-Ryul , Jin SangHoon , Lee Min-Hyung 
Published: December 2020

From the previous studies [1,2], it was well known that the voids at the interface of copper (Cu) and tin-silver (Sn-Ag) severely affects the bump reliability of flip chip packaging. And it was also suggested that impurity atoms existing in electroplated Cu film accelerate those voids formation [3]. So, in this study, we investigated the impact of leveler of Cu electroplating solution on the non-metallic impurities of electroplated Cu film and the voids at the interface of Cu and Sn-Ag solder was studied. We have found that the non-metallic impurity concentration was dominantly influenced by the adsorption characteristics of leveler. Fig. 1(a) shows the non-metallic impurity concentration in the electroplated Cu films using the electroplating solution containing different leveler. We can lower the total non-metallic impurity concentration to 14.9 ppm by changing the leveler. And we confirmed that 90% of voids at the interface of Cu and Sn-Ag solder can be reduced even after high temperature storage test at 150°C for 1000 hours, as shown in Fig. 1(b).

Reference

[1] C.Y. Liu, K.N. Tu, T.T. Sheng, C.H. Tung, D.R. Frear, P. Elenius, J. Appl. Phys. 87, 750 (2000)
[2] P.S. Teo, Y.-W. Huang, C.H. Tung, M.R. Marks, T.B. Lim, 50th Electronic Components and Technology Conference, Las Vegas, NV, USA, p. 33 (2000)
[3] T. Laurila, V. Vuorinen, J.K.Kivilahti, Mater. Sci. Eng. R, 49, 1 (2005)

Figure 1