bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrodeposition of Zn-Co-Terephthalate MOF and Its Conversion to Co-Doped ZnO Thin Films
Authors: Nakamura Tensho , Kudo Hana , Tsuda Yuki , Yoshida Tsukasa 
Published: May 2020

Energy security and sustainability are the most important challenges of mankind for their survival towards the 22nd century. While renewable electricity by solar and wind has already become so cheap, technologies for its conversion to easily storable chemical energies are urgently needed. Electrocatalysts not dependent on noble metals therefore need to be developed.
We have recently succeeded in microwave (MW)-assisted hydrothermal synthesis of Co-doped ZnO nanoparticles, which exhibit catalytic activity towards water oxidation superior to Co3O4, although the electrode prepared by paste coating faced problems of its stability due to imperfect connection of the particles [1]. Electrodeposition can overcome this problem since well crystallized, stable and perfectly conducting ZnO thin films can be obtained. However, it is not at all straightforward to dope cobalt because of the large different of solubility (K
sp = 5.92 × 10-15 and 3 × 10-17 for Co(OH)2 and Zn(OH)2, respectively), so that almost pure ZnO is solely electrodeposited even in the presence of Co2+ ions in the bath.
Taking advantage of structural flexibility of metal-organic framework (MOF) could be a possible solution to achieve co-precipitation of Zn and Co. We have recently achieved cathodic electrodeposition of Zn-terephthalate (TPA) MOF thin films by addition a TPA into the ZnO electrodeposition bath [2]. Layered MOF structure was self-assembled during precipitation by bridging of double-layered Zn hydroxide with TPA.
Herein, we report successful electrodeposition Zn-Co-TPA MOF precursor thin films and its conversion to oxides to yield Co-doped ZnO. Compositional and structural characterization as well as their electrocatalytic activities for oxygen evolution reaction (OER) are discussed.
Potentiostatic electrolysis at an F-doped SnO2 (FTO) coated glass rotating disk electrode (RDE, ω = 500 rpm) was carried out at -1.0 V (vs. Ag/AgCl) in an O2-saturated aqueous electrolyte (70ºC) containing 5 mM ZnCl2, 200 μM TPA, and 0,5 mM CoCl2, for 30min. The film was annealed at 450℃ for 1 hour, under air.
A white film electrodeposited in the presence of CoCl2 turned into green film after annealing, as expected for the formation of Co-doped ZnO. (Fig. 1a). X-ray diffraction pattern (XRD, Fig. 1b) indicates electrodeposition of Zn-TPA MOF and their conversion of ZnO after annealing both in the presence and absence of Co. The absorption spectra of the films on the other hand show clear difference between the samples, for which the one with Co and after annealing exhibit clear red-shift of onset for bandgap absorption and characteristic triple peaks at about 560, 610 and 650 nm arising from d-d transition of doped Co(II) ions (Fig. 1c). These features were commonly found for the Co-doped ZnO nanoparticles by MW reaction, so that similar or superior OER catalysis can be expected for the sample prepared by electrodeposition in this study.

Figure 1
Structure – Reactivity - Relationship in Nanostructured and Amorphous Aluminium Lanthanoid Material Libraries
Authors: Hassel Achim Walter , Shahzad Khurram , Recktenwald Dominik , Mardare Cezarina Cela , Kollender Jan Philipp , Mardare Andrei Ionut 
Published: May 2020

The lanthanoids are a consequent series of elements and with their 3 valence electrons they prefer the trivalent state while continuously filling the inner f-shell. A specific energetically stabilizing effect is observed so that the empty, the half-filled or the completely filled f-shell show extraordinary low energies resulting in a stabilizing effect so that neighboring valence states such as divalent or tetravalent can be also observed. Interestingly with increasing atomic number the atomic and ionic radii decrease - counter intuitively. As a result of the electronic shielding effect of the f-electrons the so-called lanthanoid contraction is observed.
Aluminium is another element that forms preferentially trivalent ions. A combinatorial approach in which aluminium-lanthanoid-alloys are investigated both in terms of the alloy itself but in particular for the passivity based on the mixed oxides forming on these alloys is presented here. A complex attempt was made not only to cover the various elements themselves but also their concentration ratios in material thin film libraries. These material libraries are prepared in a large preparation and analysis cluster the so-called CALMAR. Asymmetrical physical codeposition of the constituting elements is used in HV and UHV chambers to prepare these libraries and to characterize them by a scanning EDX system as well as XRD.
Theoretical considerations were used to compute the Pourbaix diagrams. Also phase diagrams of the Al-Lx alloys are consulted to identify intermetallics and regions of solid solution mixing.
Passivation studies were performed using a flow type scanning droplet cell microscope FT-SDCM. This method allows the subsequent stepwise anodization and electrochemical impedance spectroscopy characterisation of a single spot of a library having a single composition. Spatial scanning of the library yields detailed information of the systematically changing alloy compositions. To understand not only the anodic oxide formation but also the chemical and electrochemical reactions during anodization a complementary investigation of the electrolyte is performed using inductively coupled plasma spectrometry.
Various lanthanoids were mixed with aluminium and electrochemically studied. It is found that the large ionic radii mismatch is likely to cause strong amorphisation. In this way already binary alloys were found to form metallic glasses in some regions i.e. for some compositions. This has a strong impact on the passivation behavior and electrochemical stability. Some distinct intermetallic compounds in these binary alloys were found with the expected consequence for the stability.
Experimental and Computational Investigations of Pulsed Electrodeposition of Well-Adhered Nanocatalysts on Conductive Materials for Energy Applications
Authors: Karimi Shahram 
Published: May 2020

Electrical energy storage has emerged as a critical component in North America’s clean energy transformation. Vehicle electrification and integration of renewables such as wind and solar power into the grid have further underlined the importance of affordable, durable and environmentally friendly energy storage platforms. Rechargeable batteries, including Li-ion and metal-air batteries, have been receiving significant attention as well as criticism for their relatively high cost and sluggish oxygen reduction reaction, respectively. Accordingly, investigation into the development of catalysts with high activity, long life, and low cost has become an area of active research.
Nanocatalysts such as cobalt, nickel and platinum-group metals were electrodeposited on various conductive substrates, including carbon paper, carbon cloth and highly-ordered titania nanotubes (TNTs). Catalyst electrodeposition was carried out employing pulse current electrodeposition with various waveforms, low duty cycles, and high peak deposition current densities. All catalysts were systematically characterized and tested using microscopy, spectroscopy and electrochemical techniques. The presence of nanocatalysts were confirmed by SEM and XRD and were found to be 2-5 nm for platinum and platinum-group metals and 10-50 nm for nickel and cobalt on carbon substrates and TNTs, respectively.
A comprehensive mathematical model based on progressive nucleation was developed to elucidate the roles of various process parameters, including pulse waveform, peak deposition current density and duty cycle on the size and catalytic activity of the resulting nanocatalysts in different environments. The model considers some key contributing factors towards growth current and, ultimately, nucleation, including diffusion, ohmic and charge transfer phenomena as well as varying diffusion coefficients during electrodeposition. Model predictions were confirmed by experimental measurements especially on platinum-group metals deposited on carbon substrates for use in PEM fuel cells and bi-functional nanocatalysts for use in aluminum-air batteries.
Electrodeposition of ZnNi Alloys from Ethylene Glycol for Corrosion Protection
Authors: Bernasconi Roberto , Firtin Gozde , Kahyaoglu Buse , Nobili Luca , Magagnin Luca 
Published: May 2020

Zn rich ZnNi alloys electrodeposition have recently attracted the attention of researchers due to their interesting corrosion properties [1]. In particular, alloys containing Ni in the 15 - 25 % range find application in a number of industrial fields, like automotive and constructions. ZnNi is normally electrodeposited from aqueous solutions, in which plating takes place following a typical anomalous mechanism [2]. In the last few years, however, new deposition approaches have been attempted to improve ZnNi plating performances. Specifically, III generation deep eutectic solvents comprising choline chloride have been tested [3].
The present work investigates the use of non-aqueous ethylene glycol based electrolytes for the deposition of Zn rich ZnNi alloys. The use of ethylene glycol as solvent introduces many advantages with respect to aqueous solutions: low oxygen contamination, high deposits purity and no pH dependance [4]. ZnNi codeposition was studied employing cyclic voltammetry and layers were deposited under potentiostatic control. Deposition potential was varied and its influence on final composition and morphology was determined. Addition of an additive (NH4Cl) to enhance surface morphology was attempted as well [3]. Phase composition was investigated using XRD to determine the possible presence of a metastable γ-ZnNi phase, which has already been observed in the case of ZnNi plated from alkaline aqueous solution [5]. Finally, corrosion behavior of layers obtained from ethylene glycol was assessed and compared with equivalent coatings deposited from commercial aqueous solutions.
[1] M. Gavrila et al.; Surface and Coatings Technology, 123 (2-3), 164-172 (2000)
[2] G. Roventi et al.; Journal of Applied Electrochemistry 30 (2), 173–179 (2000)
[3] S Fashu et al.; Transactions of Nonferrous Metals Society of China 25 (6), 2054-2064 (2015)
[4] G. Panzeri et al.; Electrochimica Acta 271 (1), 576-581 (2018)
[5] S. Ieffa et al.; Transactions of the IMF 94, 321-324 (2014)
Prospects for Electrocatalytic Nitrate Reduction
Authors: Hatzell Marta C. , Lim JeongHoon 
Published: May 2020

There is a growing imbalance in the nitrogen cycle, which is largely due to anthropogenic activities related to transportation and agriculture. This has resulted in a significant increase in both air and water based pollutants most commonly in the form of NOx, NH3, and NO3
-. Nitrate in groundwater is growing in concern globally, as it has significant impacts on public health. Today, current treatment strategies have largely focused on centralized biological treatment at wastewater treatment facilities. While effective, this requires the waste to be transported to the centralized facilities creating a large carbon footprint. Ideally, treatment of nitrate at the point source (location of farm runoff) could aid in containing the waste dispersion and could provide a way to recover nutrients necessary for agriculture.
Electrochemical remediation through electrocatalysis has been widely investigated for decades. However, the activity and selectivity for nitrate reduction on state of the art electrocatalyst has been limited. This has been ascribed to the sluggish kinetics (multi-electron transfer processes) and competition with hydrogen evolution reaction. Here we will explore the catalytic properties that need to be obtained for electrocatlytic nitrate reduction to be realized, and will highlight the role catalyst structure will play in achieving these goals. We will also detail an energy and exergy analysis, and will discuss the role systems engineering may play in advancing electrochemical nitrate remediation.
Generation of Virtual Microstructures for the Optimization of Lithium-Ion Battery Cathodes
Authors: Joos Jochen , Schmidt Adrian , Buchele Alexander , Weber André , Ivers-Tiffée Ellen 
Published: May 2020

The microstructure of lithium-ion battery cathodes rules their performance. However, the production of a variety of cathodes with different microstructures through laboratory experiments is very expensive with respect to costs and time. Thus, model-based simulation approaches, i.e., virtual microstructures generated and analyzed on a computer, have become an important tool for microstructural optimization.
In this work, tools for the generation of realistic yet virtual microstructures are presented. Basically, three dimensional reconstructions of cathode microstructures are established by FIB tomography, and the individually shaped particles of the active material phase as well as the carbon black are extracted. A representative set of extracted particles is used to create structures with specified characteristics, such as e.g. the desired mass content of active material and conductive additive or specific particle size distributions. In combination with performance models, a preselection of promising design concepts can be conducted.
The complete workflow from the generation of realistic virtual microstructures based on 3D reconstruction via FIB tomography towards the simulation of discharge curves will be shown using the example of a commercial blend cathode consisting of the two active materials LiNiCoAlO2 (NCA) and LiCoO2 (LCO).

Figure 1
Operando Analysis of Bi/BiF3 Electrode Reaction in Li+/F- Hybrid Electrolyte By Synchrotron Radiation Diffraction
Authors: Fujimoto Hiroyuki , Kano Gentaro , Kiuchi Hisao , Shimoda Keiji , Kawasaki Mitsuo , Morigaki Ken-ichi , Kawauchi Shigehiro , Ogumi Zempachi , Abe Takeshi 
Published: May 2020

1.Introduction
In recent years, the development of innovative batteries that exceed the performance of lithium-ion batteries has been desired. One of the candidates is a fluoride shuttle battery (FSB). It is an anion-based, rechargeable batteries operating under fluoride shuttling, and rests upon the foundation of a redox-active fluoride ion transporting electrolyte of high electrochemical stability. To realize the FSB, we have developed a lactone-based Li+/F- hybrid electrolyte, in which Li+ and F- ions that normally cannot coexist in organic solvents form some complexes soluble in GBL. The thus reformed electrolyte, together with its delicate and unique anion accepting (AA) function, largely expands the negative potential window to or beyond the standard redox potential of Li+/Li. In this study, in order to clarify the electrochemical behaviors of BiF3/Bi electrode combined with the electrolyte, the operando analysis was carried out by the synchrotron radiation diffraction (SRD) measurement.
2. Experimental
The BiF3 powder mixed with acetylene-black and PVdF was used as the working electrode. The activated carbon and Ag metal were used as the counter and reference electrodes, respectively. The Al-laminated half-cell composed of above-mentioned electrodes was assembled using a newly developed hybridized electrolyte. Thus prepared cell was pre-discharged (0th cycle) in advance in the potential range of -1.5 V – 1.0 V at ca. 0.04C. Then, several charge/discharge cycles were repeated with the same conditions. SRD was measured with BL28XU beam line at Super Photon ring-8, Japan during the whole charge/discharge process. High-energy X-ray with a wavelength of 0.049592 nm was used to obtain 2D diffraction patterns. The exposure time was set to 10 s, and several thousand diffraction profiles were obtained during the discharge/charge process. In order to analyze the obtained enormous profiles data in conjunction with the charge/discharge curves and their differential curves (V-dQ/dV), an analysis software called “Profile Chaser” was newly developed. By using the software, all the profiles of electrode during charge/discharge processes are loaded automatically in the computer. The profiles were successively displayed on a monitor as a series of profiles in conjunction of compositions estimated from the charge/discharge curves, so that the profile change was traced from the monitor.
3. Results and discussions
Fig.1 shows the SRD profile changes in the discharge process of 0th and 1st cycles. In both cycles, the intensity of 111 diffraction of BiF3 decreased and that of 012 diffraction of Bi increased as the discharge reaction proceeded. However, the formation of BiF3 was hardly observed in the charge process. It indicates that the bismuth fluoride formed in the charge process is amorphous or solved in the electrolyte.

Figure 1
Development and Application of Lithium Metal Phosphate to Achieve High Power Lithium-Ion Battery
Authors: Kanno Yusuke , Yanagita Hideo , Nakajima Satoshi , Suzuki Eiko , Ushirogochi Toru 
Published: May 2020

Due to the increase of lithium-ion battery (LIB) capacity, LIBs have been widely applied to hybrid or pure electric vehicles (EVs) and stationary energy storages. Simultaneously, the requirements of LIBs performance (ex. safety, long cycle life and power performance) have also been increased. Focusing on the cathode active materials, lithium iron phosphate (LFP) is an attractive material which possesses an excellent thermal stability and long cycle life originated from its specific crystal structure of lithium metal phosphate [1]. Although the recent demand of LFP has been growing for different industrial uses, its low average potential (~3.4 V vs. Li/Li+) still remains a main issue. In this study, we developed a unique lithium metal phosphate that shows high average potential and excellent power performance. The power performance is contributed to its fast transport of lithium-ions in the original crystal structure consisted of three-dimensional framework. The synthesized material demonstrates promising electrochemical properties analyzed by different methods. Moreover, the synthesized material blended with another cathode active material results in a higher power performance of LIBs.
The lithium metal phosphate powder was synthesized by a liquid phase method. The electrode paste was prepared by mixing cathode active materials with carbon conductive agents and binders in N-methyl-2-pyrrolidone solvent. The paste was then used to prepare cathode on top of Al foil. Lithium metal foil or graphite anode electrode was used as a counter electrode. LiPF6 in organic carbonate solvent was used as electrolyte. The galvanostatic charge/discharge measurements were done at room temperature. Electrochemical impedance spectroscopy and cyclic voltammetry were used for analyzing lithium ion and electron transfer.
The experimental discharge capacity of the synthesized material matches with theoretical capacity calculated from the synthesized chemical composition, with a higher average potential than conventional LFP (~3.4 V). As for the power performance, the capacity retention rate of the fabricated LIB was over 80% at 50C discharge rate. In addition, the mixture of the synthesized material and another cathode active material showed a positive effect on the power performance of LIBs. Lastly, the synthesized material can be applied for use of inkjet printing systems attributed to its micrometer-size particle based on our accumulated technological expertise. Here, a detail discussion about the characteristics of the synthesized material will be reported in this meeting.

Reference

[1] N. Nitta et al., Mater.Today, 18, 252-264, 2015.
High-Voltage Sodium and Lithium Nitridophosphates axMy(PO3)3n As Cathode Materials for Sodium-Ion and Lithium-Ion Batteries
Authors: Wizner Agnieszka , Reynaud Marine , López del Amo Juan Miguel , Lian Jian Xiang , Bonilla Francisco , Carrasco Javier , Armand Michel , Rojo Teófilo , Casas-Cabanas Montse 
Published: May 2020

Polyanionic compounds stand out as attractive candidates for electrode materials in Na-ion and Li-ion batteries due to their stable 3D framework.1 Furthermore, according to theoretical calculations, N-substituted polyanionic compounds should enable the use of more than one redox couple of transition metals due to the lowering their working voltage.2

Nitridophosphates, with general formula NaxMy(PO3)3N, exhibit an open 3D structure that facilitates the migration of ions at room temperature and enables stable cycling.3,4 In particular, our research has uncovered the remarkably high working voltage of Na3V(PO3)3N (4.0 V vs Na+/Na0 , Figure 1) which, together with Na7V3(P2O7)4, is the highest operating voltage for Na-ion cathode material for the VIV+/VIII+ redox couple.5,6 Moreover, Na3V(PO3)3N can also be used as a cathode in a hybrid Lithium-ion configuration.
The Li counterpart Li3V(PO3)3N, can be prepared by chemical ion exchange. Its 6Li ssNMR spectrum exhibits three different peaks that have been assigned to the three independent Li sites and the Li mobility between those sites was probed by 2D exchange spectroscopy (EXSY), as shown in Figure 1c.
Aiming to lower the cost and improve the electrochemistry we have further explored the family of nitridophosphates. Seeking for redox-active transition metal we focused on economical and earth abundant 3d metals. Our studies resulted with improving the electrochemical performance of Na2Fe2(PO3)3N vs Na and synthesizing for the first time cobalt nitridophosphate, Na2Co2(PO3)3N with expected electrochemical activity at ~4.5V vs Na+/Na0. Endeavoring to obtain a manganese nitridophosphate we have discovered a new family of compounds which will be also shown.7

1. C. Masquelier and L. Croguennec, Chem. Rev. 113, 6552 (2013).
2. M. Armand and M.E.A. y de Dompablo, J. Mater. Chem. 21, 10026 (2011).
3. J. Liu, X. Yu, E. Hu, K.-W. Nam, X.-Q. Yang, and P.G. Khalifah, Chem. Mater. 25, 3929 (2013).
4. J. Liu, D. Chang, P. Whitfield, Y. Janssen, X. Yu, Y. Zhou, J. Bai, J. Ko, K.-W. Nam, L. Wu, Y. Zhu, M. Feygenson, G. Amatucci, A. Van der Ven, X.-Q. Yang, and P. Khalifah, Chem. Mater. 26, 3295 (2014).
5. M. Reynaud, A. Wizner, N. A. Katcho, L.C. Loaiza, M. Galceran, J. Carrasco, T. Rojo, M. Armand, and M. Casas-Cabanas, Electrochemistry Communications 84, 14 (2017).
6. C. Deng, S. Zhang, and B. Zhao, Energy Storage Materials 4, 71 (2016).
7. A. Wizner, M. Reynaud, J.X. Lian, F. Bonilla, J.-M. Lopez del Amo, J. Carrasco, T. Rojo, M. Armand and M. Casas-Cabanas, submitted.

Figure 1