bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Characterization of a Dithionite / Air Fuel Cell
Authors: Noack Jens , Tübke Jens , Pinkwart Karsten 
Published: February 2020

With the increase of renewable energy sources in an electrical network, the need for energy storage increases. Depending on the application, there are different ways to store electrical energy. For electrochemical energy storage options exist in the form of batteries, redox flow batteries and fuel cells coupled with electrolysis. The longer the storage time, the lower the cost of energy storage medium must be in order to be competitive with other technologies. Batteries and redox flow batteries use reversible electrochemical reactions, fuel cells do not normally what makes specially adapted electrolysers required. Wherever possible, simple and rapid electrochemical reactions for the reversal of the reactions are required, as for example are found in the redox couple H2/2H+. The reactions of organic redox couples of DMFC and DEFC can be electrochemically not reversed. Another way could be combinations of anodes of dissolved ions with an oxygen cathode, thereby “burning” the salt solutions which results in direct ion liquid fuel cells. A representative is the vanadium / oxygen fuel cell in which divalent vanadium ions are oxidized to trivalent at the anode by means of oxygen at the cathode [1]. The reactions can be reversed by vanadium / water electrolysis in the same cell as a reversible fuel cell (redox flow battery) [2, 3] or externally with a separate electrolysis cell [4].
Here we would like to report a work in which we have built and studied an alkaline fuel cell with the inexpensive redox couple dithionite / sulfite.
Anode: S2O4
2- + 4 OH- -> 2 SO3
2- + 2 H2O + 2 e- E0= -0.294 V
Cathode: O2 + 2 H2O + 4 e- -> 4 OH- E0= +1.227 V
Cell: 2 S2O4
2- + O2 + 4 OH- -> 4 SO3
2- + 2 H2O E = 1.530 V
As with the VOFC the reactions in a separate or the same cell may be reversed, and thus serve as an energy storage. For investigating the feasibility of such a cell a carbon-based anode and a platinum catalyst cathode for the ORR was used. The investigations were carried out by means of polarization curves, discharge tests and impedance spectroscopy using the cell voltage and the half-cell potentials and showed a maximum power density of 2 mW/cm² at room temperature. Under these conditions the oxidation of dithionite at carbon was much slower than the ORR. With a 0.85 M Na2S2O4the cell reached 12.4% energy efficiency and an energy density of 8.6 Wh/L.
1 C. Menictas, M. Skyllas-Kazacos, Journal of Applied Electrochemistry 2011, 41, 1223–1232.
2 S. S. Hosseiny, M. Saakes, M. Wessling, Electrochemistry Communications 2011, 13, 751–754.
3 J. grosse Austing, C. Nunes Kirchner, E.-M. Hammer, L. Komsiyska, G. Wittstock, Journal of Power Sources 2015, 273, 1163–1170.
4 J. Noack, T. Roth, M. Hihn, J. Tuebke, The 7th International Green Energy Conference & The DNL 1st Conference on Clean Energy, Dalian, China, 2012

Figure 1
Nickel Selenide As High-Efficiency Catalyst for Oxygen Evolution Reaction
Authors: Swesi Abdurazag , Masud Jahangir , Nath Manashi 
Published: February 2020

Electrolytic water splitting is considered to be clean energy generation and a substitute for fossil fuels and oxygen evolution reaction (OER) is an important reaction involved in water splitting. However, OER typically being a 4 electron process requiring O – O bond formation is a kinetically slow process typically requiring catalysts.1Identifying more-efficient, stable, earth-abundant catalysts for the OER has long been researched. Recently, Ni-oxide based OER electrocatalysts were found to exhibit high efficiency, and it was stated that the catalytic performance can be further tuned by increasing covalency in the metal-oxygen bonds. The catalytic properties of the metal oxides can also be influenced through other variables of the electrodeposition reaction such as the total and relative concentration(s) and composition(s) of dissolved metal salts and extra electrolytes, the pH, and the duration of the electrodeposition current.2 Here we report, for the first time, a metal-rich form of Ni-selenide, Nickel subselenide, Ni3Se2 as a potential oxygen evolution electrocatalyst in alkaline condition. The Ni3Se2 phase has a structure similar to the sulfur mineral Heazlewoodite, which contains metal – metal bonding. The electrocatalytic activities of Ni3Se2towards OER was seen to be at par with or even superior to the transition metal oxide based electrocatalyst in terms of onset overpotential for O2 evolution as well as overpotential to reach a current density of 10 mA/cm2 (observed at 290 mV).
The electrocatalytic Ni3Se2 were grown by electrodeposition on conducting substrates and the deposition parameters including pH of the electrolytic bath, deposition potential, and substrate composition were seen to have some influence on the catalytic activity. Annealing of the as-deposited electrocatalytic films in an inert atmosphere enhanced their catalytic efficiencies by decreasing the overpotential (@10 mA/cm2) as well increasing the current density. In addition to low overpotentials, these Ni3Se2 electrodeposited films were seen to be exceptionally stable under conditions of continuous O2 evolution for extended period (48 – 66 h). The structure and morphology of these films has been characterized with powder X-ray diffraction, Scanning and Transmission electron microscopy, Raman, and X-ray photoelectron spectroscopy. We will discuss in detail the electrochemical and structural characterizations of these films along with catalytic activities.
References:
1. E. Mirzakulova, R. Khatmullin, J. Walpita, T. Corrigan, N. M. Vargas-Barbosa, S. Vyas, S. Oottikkal, S. F. Manzer, C. M. Hadad, and K. D. Glusac, Nature Chem. 2012, 4, 794.
2 McCrory, C. C. L.; Jung, S. H.; Peters, J. C.; Jaramillo, T. F. J. Am. Chem. Soc. 2013, 135, 16977.
Combined Experimental and Computational Approach for Rational Design of Bio-Nano Interfaces
Authors: Babanova Sofia , Matanovic Ivana , Chavez Madelaine Seow , Atanassov Plamen 
Published: February 2020

Various approaches have been developed in the last 5 years regarding targeted enzyme orientation on the electrode surface but no explanation of enzyme orientation on electron transfer properties have been provided. The same can be said about the utilization of mediators for enhancement of the interfacial electron transfer. Facing this fundamental challenge we started using computational approaches along with experimental efforts to gain knowledge of the underlying processes.
In our computational and experimental benchmark studies soluble PQQ-dependent glucose dehydrogenase (PQQ-sGDH) have been explored since this enzyme is known as capable of direct electron transfer (DET). Various techniques for PQQ-sGDH immobilization and/or enhanced electron transfer have been developed over the years and a key question regarding the “proper” orientation of PQQ-sGDH has been raised. Should the substrate-binding pocket and thus PQQ be placed facing the electrode surface or it should be fully exposed to the electrolyte?
To resolve this question and to enhance the electron transfer at the enzyme-electrode interface, quinones were explored in solution and immobilized on carbon support material. In both cases the current densities generated form the glucose oxidation through PQQ-sGDH were increased from 1.5 to 5 times depending on the properties of the explored quinones. In addition to the electrochemical characterization of the designed enzymatic anodes, molecular computational calculations, such as Density Functional Theory (DFT) and Molecular Docking Simulations, were used to gain insight into interactions between the quinones and PQQ-sGDH from one hand and the quinones and the support material, from another (Fig. 1). The role of the two types of benzoquinones, 1,2- and 1,4-benzoquinone, and ubiquinone in the operation and mechanism of the electron transfer in PQQ-sGDH anodes has been addressed1.
It was established that the higher electrochemical performance of PQQ-sGDH anodes in the presence of free 1,2- and 1,4-benzoquinones is due to the smaller distance between these molecules and the enzyme cofactor (PQQ). It was proposed that when 1,4-benzoquinone is adsorbed, it plays the role of a mediator as a result of its high electron transfer rate ability and smaller PQQ-quinone distance. At the same time when 1,2-benzoquinone is adsorbed on the electrode surface, the enzyme will transfer the electrons directly to the support and the modifier will mostly play the role of an orienting agent. Similar conclusion can be made for the PQQ-sGDH anode modified with physically adsorbed ubiquinone for which purely orientation role was proposed.
1.Babanova, S., Matanovic, I. & Atanassov, P. Quinone-modified surfaces for enhanced enzyme-electrode interactions in PQQ-dependent glucose dehydrogenase anodes. Chem. Electro. Chem.
1, 2017–2028 (2014).

Figure 1
Electrochemical Investigations of Aromatic Hydrocarbons in Adiponitrile
Authors: Cheek Graham T. 
Published: February 2020

Introduction
Recent work from this laboratory has shown that adiponitrile (NCCH2CH2CH2CH2CN) / tetraethylammonium tetrafluoroborate (TEA BF4) is a versatile solvent system for organic electrochemistry (1,2). The extraordinary 7-Volt potential range noted in earlier work (3) has been confirmed and applied to measurement of water (1) and electrodeposition of metals (4). The +5 V vs Ag/AgCl potential limit allows another 2 volts for study, compared to that of most other solvents. The present paper addresses the usefulness of the positive potential region for oxidation of aromatic hydrocarbons.
Experimental
Adiponitrile was purchased from Sigma-Aldrich, and tetraethylammonium tetrafluoroborate was purchased from Southwestern Analytical Chemicals. Cyclic voltammograms were obtained on a PAR 283 potentiostat using PowerSuiteTMsoftware. Potentials are referenced against a Ag/AgCl reference electrode (1).
Results and Discussion
A cyclic voltammogram of 10 mM naphthalene in adiponitrile / 0.2 M TEA BF4 is shown in Figure 1. The reversible reduction of naphthalene is observed at -2.5 V, followed by an irreversible oxidation process at +1.74 V vs Ag/AgCl. Scan reversal at +2.00 V shows no reduction current associated with this oxidation process at 100 mV/s. Continuation of the potential scan to +5.0 V, as shown, results in considerable oxidation current up to the positive potential limit. This charge passage, however, significantly lessens the peak currents for the redox process at -2.5 V on the following sweep, implying some electrode filming in the highly positive potential range. Naphthalene oxidation has also been studied in acetonitrile (5), and the results were similar to those in the present study although the positive scan limit in acetonitrile was only +1.75 V vs SCE. In the acetonitrile study (5), the irreversible nature of naphthalene oxidation was attributed to rapid coupling of naphthalene radical cations. The results of the present study show that the entire positive potential range in adiponitrile is available for study of the representative aromatic hydrocarbon naphthalene. It is also intended to present results for other aromatic systems.
References
1. G. T. Cheek, ECS Trans., 58(46), 45-51 (2014).
2. G. T. Cheek, ECS Trans., 61(30), 19-24 (2014).
3. H. Duncan, N. Salem, and Y. Abu-Lebdeh, J. Electrochem. Soc., 160(6), A838-A848.
4. G. T. Cheek, ECS Trans., 61(24), 9-14 (2014).
5. M. N. Cortona, N. Vettorazzi, J. J. Silber, and L. Sereno, J. Electroanal. Chem., 394, 245-251 (1995).
Figure 1. Cyclic voltammogram of 10 mM naphthalene at glassy carbon in adiponitrile / 0.2 M tetraethylammonium tetrafluoroborate.
Initial negative-going sweep from 0.00 V vs Ag/AgCl; 100 mV/s

Figure 1
Organized Light Harvesting Photosystem I Layers on a Cytochrome C for the Construction of New Photobioelectrodes
Authors: Feifel Sven Christian , Stieger Kai , Lokstein Heiko , Lisdat Fred 
Published: February 2020

Artificial approaches to mimick natural photosynthesis are an emerging field of research with impact on photobiocatalytic systems and photobiovoltaic applications. Herein, we manage the assembly of two heterologous proteins exhibiting key features for the usage in biohybrid light-converting electrode systems. We combine the photon converting pigment-protein super-complex - photosystem I (PSI), from natural photosynthesis of cyanobacteria1 - with a small electron carrier, cytochrome c (cyt c) from the respiratory chain, in mono- and multilayer arrangements. Often, PSI has a random orientation when self-assembled on surfaces and provides a slow direct electron transfer (DET).2 Our strategy to overcome these issues, is to assemble PSI with the help of electron carriers similar to native electron transport. This provides two advantages: (1) redox protein mediated indirect electron transfer (IET) may yield high photocurrents, due to rather small electron tunneling distances; (2) redox proteins can be considered as an assembly template on which PSI can adsorb efficiently by reason of electrostatic and/or native affinity, which has been studied by surface plasmon resonance (SPR). By this approach, we developed photoreactive protein layers on electrodes, which have a potential-driven cathodic photocurrent to reduce the PSI after light induced electron-hole-pair separation. The study determines the role of cyt c in such organised films, which works as a template but also show the ability to connect and wire the PSI with the electrode.3 This is also valid in a multilayer arrangement with PSI far away from the electrode surface. The system can be seen as a network with electron conducting elements forming a protein 3D architecture. In order to increase the photocurrent of such electrodes, a multilayer approach and a time-dependend self-growth of cyt c/PSI-architectures was developed. The presented work can be considered as a contribution to current research in order to develop organised protein films for the effective conversion of light into electrical and/or chemical energy.
(1) Grotjohann, I.; Fromme, P. Photosynth. Res. 2005, 85 (1), 51−72.
(2) Ciesielski, P. N. et al. J. Phys.
Chem. A
115, 3326–34 (2011).
(3) Stieger, K. R.; Feifel, S. C. et al. Phys. Chem. Chem. Phys. 16, 15667-15674 (2014).
Thermal Stability Studies in Charged Layered Sodium Transition Metal Oxide Cathode Materials for Na-Ion Batteries
Authors: Bak Seong-Min , Zhou Yongning , Hu Enyuan , Yu Xiqian , Yang Xiao-Qing 
Published: February 2020

Layered alkali transition metal oxides (i.e., LiMO2 and NaMO2, M=transition metal) are the premier class of cathode materials in lithium- and sodium-ion battery system. The safety characteristics of LiMO2 cathode based LIBs are one of the most critical barriers to be overcome for the large scale application such as EV. One of the main reasons that might cause safety hazards of the LIB is associated with the thermal instability of charged Li1-xMO2 cathode materials, which is related to the occurrence of exothermic reactions between flammable electrolyte and liberating oxygen from charged Li1-xMO2 at high temperature. Based on the structural homology between the layered LiMO2 and NaMO2, we expect that the investigation of thermal stability of charged Na1-xMO2cathode materials is also important for the practical use of SIBs. However, few attentions have been paid on safety issue of SIBs.
In this study, the thermal stability of charged Na1-xMO2 cathode materials is investigated by using combined in situ time-resolved X-ray diffraction and mass spectroscopy (TR-XRD/MS), which allows simultaneous observation of the structural changes and gas species that are evolved during thermal decomposition of charged cathode materials, especially O2 gas in our interest. In addition, the ex situ/in situ X-ray absorption spectroscopy (XAS) has been also utilized to look at the local and electronic structural changes occurring during thermal decomposition in an elemental selective way. By utilizing combined X-ray techniques, we are able to get better understanding of structural and electronic structure changes in charged cathode materials during thermal decomposition. In this presentation, the thermal decomposition behavior of charged Na1-xMO2(M=Co, Cr) cathodes will be covered.
Acknowledgement
The work done at Brookhaven National Lab. was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the U.S. DOE under Contract No. DE-SC0012704.
3D-Nanostructures-Path to High Capacity Lithium Batteries with Ultimate Safety
Authors: Prochazka Jan , Stary Radomir , Pavlik Jiri , Zukalova Marketa 
Published: February 2020

Thin film technologies (2D) producing lithium ion accumulators have nearly been optimized. The capacity limits are given by the thickness of the components, especially the foils and separators.
A significant increase of lithium battery capacity is achievable by nanostructured morphologies of the electrodes and extending of the electrode thickness from micrometers (2D) to millimeters (3D).
The HE3DA® battery technology is based on nanomaterials, special inorganic separators and several millimeters thick electrodes. It is ideal for production of high capacity batteries and large energy storage modules.
This fully inorganic battery does not contain any organic melting parts, demonstrates a very low internal resistance, allows easy degassing and shows a number of other advantages that are not possible to utilize by the conventional 2D technologies. This 3D battery technology provides an inherited safety to the batteries, enabling construction of very large cells on MWh level and modules on hundreds of MWh scale. HE3DA® system significantly simplifies the BMS.
In Operando Li+- Activity Measurements in Lithium Ion Batteries - a Method to Develop and Optimize Safe Operating Strategies Even at Unfavourable Conditions
Authors: Hogg Bjoern-Ingo , Wohlfahrt-Mehrens Margret 
Published: February 2020

The deposition of lithium on the surface of graphitic anodes in Lithium-ion batteries is a major concern about safety and lifetime of lithium-ion batteries.
The deposition can be caused by high anodic overpotentials at low temperatures or exceeding a critical lithium ion concentration at the graphite particle surface. The prediction of the onset of lithium deposition by modelling is rather difficult because there are no reported values for the Li+ activity in the electrolyte or their changes during lithium ion insertion into graphite. Furthermore the modelling of the Li+ activity in the electrolyte is quite challenging because the needed parameters like the diffusion coefficient of Li+inside the particles depend strongly on the state of charge and the absolute value on the measuring method respectively the texture of the electrode coating [1].
The critical Li+ activity in the electrolyte in matters of a lithium deposition follows from the concentration dependency of the Li/Li+potential, which is described by the Nernst equation.
In the present study, we take advantage of the concentration dependency and develop a 4-electrode cell design (Figure 1a), which allows to measure potential changes of the metallic lithium reference electrode of the standard three electrode setup.
The potential shifts of the metallic lithium reference correlate directly with changes in the Li+ activity in the electrolyte. We studied the interaction of lithium transport and reaction kinetics in dependency of current density, temperature and active material of the anode and the cathode. The measurements indicate a direct correlation between changes in anodic and cathodic reaction kinetics and the Li+concentration in the electrolyte (Figure 1b).
Based on the knowledge of the Li+activity and its variation, we were able to improve an operation strategy for Lithium-Ion batteries and match the cell components with each other in terms of avoiding lithium deposition.

References

[1]B: Markovsky, M.D. Levi and D. Aurbach, Electrochimica Acta ,
43, 2287(1998)

Figure 1
Failure Mechanism Investigation of Commercial LiFePO4 Cells in Different Operating Conditions
Authors: Liu Yadong , Liu Qi , Li Zhe-Fei , Yang Fan , Ren Yang , Lu Wenquan , Xie Jian 
Published: February 2020

The rapid growth of the Li-ion battery (LIB) market has greatly driven research on LIBs, particularly on LIB failure mechanisms under different operating conditions (long-term cycling, overcharge, over-discharge, high temperatures, low temperatures, etc.) due to safety issues1. Up to now, there are only very few of reports on the capacity fade mechanisms in the commercial batteries2. It is paramount of scientific and engineering importance to understand the microstructure evolution during normal cycle in the commercial cells. To our knowledge, in situ monitoring of microstructure evolution during the capacity fade process in either a commercial battery or lab-made batteries has never been reported before.
In this work, the capacity fade/failure processes of commercial 18650 LiFePO4 cell during the long term normal charge/discharge, overcharge, and over-discharge cycling was systematically investigated respectively. The commercial 18650 LiFePO4cells (A123 Systems) were chosen to be cycled for all cycling conditions until these cells reach 80% of initial capacity (typical criteria for EV application) or cannot be charged/discharged.
The cells were in situ characterized and the microstructure of the electrodes was investigated using synchrotron high-energy X-ray diffraction during long term normal cycling and overcharge/over-discharge cycling conditions. Synchrotron high-energy X-rays with photon energy of 115 KeV are capable of penetrate through thick samples, which allows us to probe commercial 18650 LiFePO4 cells without any cell modification and the results are presented herein. The result of 18650 cell after 2500 cycles is shown in Fig. 1. Our in situ experiment result show that loss of the active lithium source in the system is the primary cause of the capacity fade and the appearance of the inactive FePO4phase is proportional to the decrease of available lithium source during cycling.
Electrochemical Impedance Spectroscopy (EIS) is a powerful and quick analytical and diagnostic tool that can be used to study the internal resistance of Li-ion batteries during long-term normal cycling or overcharge/ over-discharge cycling3. The EIS results during overcharge and over-discharge process are shown in Fig. 2 and 3 respectively, and the de-convoluted Ohmic resistance, solid electrolyte interphase (SEI) resistance, and Warburg Coefficient, change with cycle number in some patterns, indicating the occurrence of corrosion of the current collector, SEI breakdown/decomposition and reformation, and the development of diffusion barriers of Li+ in the electrode, respectively. These parameters are associated with failure and can be used as indicators of incoming failure. Overall, EIS can be used as an effective and reliable tool to monitor the state of health, predict incoming failure of the LIB cells, and issue a warning before failure without disturbing the operation of the cells.

Figure 1