bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensing Interfaces for Bioelectrocatalytic Stimulated Release
Authors: Masi Madeline , Bollella Paolo , Katz Evgeny 
Published: May 2020

Signal-stimulated (bio)molecular release has been extensively studied and reported in numerous research papers, reviews and books,1 being motivated by various biomedical and biotechnological applications. Among many other molecular, biomolecular and nano-size species, DNA molecules have been studied for the signal-controlled release, being highly important for gene delivery therapy, biosensors, biochips, unconventional biocomputing, and for many other applications. Various signals triggering DNA release have been used including application of altering electromagnetic field, photochemical capture and release of DNA, thermally stimulated release of DNA, etc. Electrochemically triggered DNA release is particularly attractive due to its simple realization and versatility. Specifically, these developed systems are designed for different release processes triggered by various signals (electrical, biomolecular, illumination, etc.), thus representing a general interfacial platform for controlled release of different biomolecules and nano-size species.2

Herein, we report on the DNA releasing system controlled by local/interfacial pH changes triggered by a very small potential applied to reduce oxygen bioelectrocatalytically with the help of immobilized bilirubin oxidase (Box). Notably, the DNA release was only a convenient model, while the developed approach can be adapted to the electrically stimulated release of any negatively charged (bio)molecules or nano-species.3

1. Li, X.; Jasti, B. R. Design of Controlled Release Drug Delivery Systems, McGraw-Hill Education, New York, 2005.
2. Masi, M.; Bollella, P.; Katz, E. Electroanalysis
2019, 31, in press, published on-line (DOI: 10.1002/elan.201900377).
3. Masi, M.; Bollella, P.; Katz, E. ACS Applied Materials and Interfaces
2019, Submitted.
(Invited) Switching on Elctrocatalytic Activity for Synthetic Fuel Production
Authors: Irvine John 
Published: May 2020

The greatest challenge facing Solid oxide cells (SOC), in both fuel and electrolysis cell modes (i.e SOFCs and SOECs) is to deliver high, long-lasting electrocatalytic activity while ensuring cost and time-efficient electrode manufacture. Ultimately, this can best be achieved by growing appropriate nanoarchitectures under operationally relevant conditions, rather than through intricate ex situ procedures.
In our approach, metal particles are grown directly from the oxide support though in situ redox exsolution. We demonstrated that by understanding and manipulating the surface chemistry of an oxide support with adequately designed bulk (non)stoichiometry, one can control the size, distribution and surface coverage of produced particles. We also revealed that the emergent particles are generally epitaxially socketed in the parent perovskite which appears to be the underlying origin of their remarkable stability, including unique resistance of metal particles to agglomeration and to hydrocarbon coking, whilst retaining catalytic activit.
Operando redox treatments yield emergent nanomaterials at potentials in excess of 2V. Here we apply this technique to drive steam, CO2 and coelectrolysis processes at emergent metals and alloy particles.
High-Temperature Co-Electrolysis
Authors: de Haart L.G.J. , Dittrich L. , Jaekel E. E. , Nohl M. , Foit S. R. , Vinke I. C. , Eichel R.-a. 
Published: May 2020

High-temperature Solid Oxide Electrolysis Cells (SOECs) possess the unique property to convert carbon dioxide and/or steam with a faradaic efficiency of 1 into carbon monoxide and/or hydrogen, respectively. High-temperature co-electrolysis of steam and carbon dioxide offers a suitable technology to provide 'white' syngas. Syngas, a mixture of hydrogen and carbon monoxide, as well as pure carbon monoxide are used in chemical industry for the synthesis of many basic chemicals as well as synfuels. Using renewable energy sources and the climate gas CO2 the high-temperature CO2 and co-electrolysis technology presents a sustainable alternative to conventional processes. The technology of co-electrolysis allows the adjustment of the H2 to CO ratio required for various down-stream catalytic processes in one step.
Investigations of the high-temperature electrolysis of steam or CO2 and the co-electrolysis of a mixture of both in the feed gas were performed on so-called fuel electrode supported cells consisting of a 8mol% yttria stabilized zirconia (8YSZ) electrolyte, a Ni/8YSZ support and fuel electrode and a (La,Sr)(Co,Fe)O3 air electrode. The experiments showed that the performance of the cell during CO2 electrolysis is lower than for steam and co-electrolysis, as is shown in the Figure. The performance can be characterized by the slope of the current-voltage curve, i.e. the area specific resistance (ASR). For the CO2 electrolysis the ASR at 900 °C and 1.5 A·cm-2 amounts to 410 mΩ·cm-2. For steam and co-electrolysis, the ASR values are nearly the same: 245 mΩ·cm-2. The lower performance for CO2 electrolysis is attributed to the slower kinetics of the CO2 reduction reaction compared to the H2O reduction reaction. Similar observations were made in fuel cell operation, in which the CO oxidation reaction is around a factor 5 slower than the H2 oxidation reaction. The similar ASR values for steam and co-electrolysis are attributed to the occurrence of the reverse water gas shift (RWGS) reaction, in which CO2 and H2 react to CO and H2O during co-electrolysis. The slower kinetics of the CO2 reduction reaction are by-passed in the RWGS reaction using the hydrogen generated through the steam reduction.
Further experiments were conducted to investigate the role and importance of the RWGS reaction during co-electrolysis. At the boundary to pure CO2 electrolysis, the performance of feed gas mixtures with low steam contents were investigated. First results show a significant increase of the area specific resistance at a reduced (RWGS) equilibrium steam concentration of about 5 %. Above 15 % steam in the feed gas (in the RWGS equilibrium) the ASR is no longer influenced by the feed gas composition and similar to that of pure steam electrolysis. Experimental results are furthermore compared to theoretical calculations of syngas production on a thermodynamic and partially kinetic level.

Figure 1
Effect of Carbon Capture Endurance Conditions on Performance and Stability of Molten Carbonate Fuel Cell Cathode Electrode
Authors: Hilmi Abdelkader , Geary Timothy C , Franco Adam , Rosen Jonathan , Barckholtz Tim 
Published: May 2020

Introduction
The molten carbonate fuel cell (MCFC) is one of the most advanced high-temperature and clean power generating devices. To date >8 billion kWh of electricity has been produced commercially using this new technology. The high operating temperature of MCFC (550-650 °C) dramatically improves the reaction kinetics and eliminates the need for a noble metal catalyst. The electrochemical reactions taking place during cell operation involve the CO2 transfer from cathode to anode in the form of carbonate ions (Figure 1). Therefore, MCFC stack technology can be used for power generation and simultaneously, as an effective CO2 separator. MCFC systems can be combined with conventional combustion-powered generators (coal and/or natural gas based power plants) to efficiently separate CO2 in the exhaust gas and produce additional electricity.
The state of the art MCFC cathode is porous lithiated nickel oxide. The cathode stability and performance are affected by several factors such as gas composition, temperature, electrode structure and electrolyte chemistry. To ensure long-term performance and material stability against NiO dissolution, polarization loss, and carbon capture efficiency, major considerations need to be taken into account in material selection, operating conditions, and electrode structure design.
FCE has tested many single cells (250 cm2) and technology stacks (30 kW) under carbon capture operating conditions (4-5% CO2 in the cathode inlet as opposed to >15% in baseline MCFC systems) to understand parameters affecting performance, life, and to investigate design solutions for further enhancement. Figure 2 highlights the effect of CO2 concentration on the cathode lithiation. These measurements were conducted using an out-of-cell test (OCT) where cathode samples were exposed to different oxidizing environments. It appears that lean-CO2 gas atmospheres (<5%CO2) lead to increased lithium content in the NiO cathode. This may impact the electrolyte distribution and the cathode microstructure. Therefore, the electrolyte inventory (fill level), the lithium content and the basicity need to be considered to achieving optimal operating conditions.
This paper will review the cathode material stability, microstructure, and durability under long-term carbon-capture operations. The effect of parameters such as electrolyte fill, gas composition, and electrolyte chemistry, as well as approaches to enhance the CO2 capture efficiency and life, will be discussed.

Figure 1
(Invited) Controlling the Size and Dispersion of Exsolved Catalyst Particles By Electrochemistry and By Strain
Authors: Yildiz Bilge , Dimitrakopoulos Georgios , Wang Jiayue , Fan Weiwei , Kyriakou Vasileios , Ghoniem Ahmed F. , Li Ju 
Published: May 2020

Increasing the performance of Solid Oxide Electrolysis Cells (SOECs) for the production of hydrogen (H2) from water (H2O) splitting requires the use of cathodes with low polarization resistance. In-situ growth of metal catalysts from perovskite oxides (termed catalyst exsolution) has been proposed as a means to decorate the porous electrode with highly dispersed, nanometer-sized catalytic particles [1-3]. These particles are highly active towards reactions of interest and show increased resistance to agglomeration due to their socketed nature [4].
In this work, we investigate the in-situ, on demand exsolution of catalysts by using fuel and electrochemistry as a means to decrease the temperature and duration required to grow catalytic particles on the surface of electrodes. We study the performance, stability, particle morphology and distribution as a function of electrochemical polarization applied at the electrode. Substantial improvement of reaction kinetics is found, consistent with previous reports [5]. In addition, we probe the effect of electrochemical and temperature conditions on the particle size, shape and distribution. In addition, we propose tuning the reducibility of parent oxides to be a good strategy in controlling the size and dispersion of the exsolved particles, and demonstrate this approach on epitaxial perovskite thin films. Moreover, our observations suggest oxygen vacancies to be the potential nucleation sites of the exsolved particles.
The present study provides a new direction towards the generation of nanoparticle-size catalysts on the surface of perovskite oxides given the increasing demand for active and durable catalysts in the field of solid oxide cells and in other energy and fuels conversion processes.
References:
[1] G. Tsekouras et. al. Energy Environ. Sci., 2013, 6, 256–266
[2] Y. Sun et. al. J. Mater. Chem. A, 2015, 3, 11048–11056
[3] G. Dimitrakopoulos et. al. Sustainable Energy & Fuels 2019, 3, 2347-2355
[4] D. Neagu et. al. Nature Communications 8:1855 (2017)
[5] J. Myung et. al. Nature 537 (2016) 528-531
(Invited) Exchanging Degradation for Durability: Accelerated Stress Test Protocols for Solid Oxide Fuel Cells and Electrolysers
Authors: McPhail Stephen J. , Laurencin Jérôme , Hagen Anke , Leon Aline , Van Herle Jan , Vladikova Daria , Montinaro Dario , Piccardo Paolo , Polverino Pierpaolo , Herbrig Kai 
Published: May 2020

The longer lifetimes of solid oxide cells (SOC) – obtained and still required, both in fuel cell and electrolysis operation – exacerbate the need for accelerated stress tests, since neither reliable degradation models are currently available nor validated methodologies to evaluate expected stack durability in a practical timeframe. The project AD ASTRA ( “HArnessing Degradation mechanisms to prescribe Accelerated Stress Tests for the Realization of SOC lifetime prediction Algorithms”) started operations to tackle this on January 1st 2019, funded by the European Fuel Cells and Hydrogen Joint Undertaking.
Generally, a great number of operational parameters influence SOC degradation during lifetime, each contributing according to characteristic times and intensities, often in convoluted or even contrasting fashion. Aggravation of test input parameters can thus lead to non-representative accelerated degradation of a component where concurring effects are differently influenced, leading to a biased end state of the component investigate.
To systematically address, harness and accelerate the selected failure modes, a matrix was set up of degradation mechanisms, test items, test procedures and characterization methods, that was translated to protocols in such a way that consistent measurement data are generated, helping subsequent analysis and correlation of phenomena and parameters by the project’s modelling and simulation activities.
The testing approach consists of a dual-focus campaign targeting:
• macroscopic stack testing procedures, where short stacks will be operated in situ, in aggravated conditions with the objective of identifying test settings that will stress the stack in a representative way but minimizing testing time and resource expenditure
• specific component ageing tests, to reproduce (ex-situ) the degraded condition of critical stack components or interfaces in a faster time, based on analysis of the components extracted from stacks that have been field-tested.
A radical innovation of the project consists in the integration of these two methods: components specifically aged ex situ assembled into otherwise “new” stacks for in-situ testing, so that their effect on stack performance can be easily isolated from other components that in real-world conditions would also degrade. These tests allow to observe from the start (t=0) the end-of-service stack degradation, radically reducing in-situ testing time and providing powerful means to validate models simulating the long-term effects of component degradation in a stack.
A Holistic Approach to Develop Novel Processes for the Sustainable Electrochemical Synthesis of Fuels and Chemicals
Authors: Khanipour Peyman , Derleth Felix , Reichert Andreas M. , Katsounaros Ioannis 
Published: May 2020

Electrochemical synthesis can become a sustainable solution for the production of fuels and fine chemicals, because (i) it can enable a revolutionary transition in chemical production away from fossil fuels if the required electricity is provided by renewables (ii) it can address the mismatch between intermittent supply and demand of energy, and (iii) it can enable the decentralized, onsite production of chemicals [1, 2]. The various promising electrochemical synthesis processes are at different levels of technological maturity, therefore, to accelerate developments in the field we need to follow holistic approaches that address all material, system or time scales.
Here, we describe a systematic methodology for the development of electrochemical process. We first screen various electrodes and potentials, utilizing an own-developed, internationally unique method for the real-time characterization of reaction products [3]. This method is based on coupling of electrochemical flow cells with delicate mass spectrometry techniques. At a second stage, promising materials are examined at selected constant potentials to quantify activity, selectivity, and durability over time. In this case, the electrochemical cell is coupled with online or offline analytical techniques for the quantification of production rates, selectivities, or faradaic efficiencies. Finally, we transfer the gained understanding from the previous two steps to design an applied electrochemical reactor that can carry out the desired process under industrially relevant conditions. The approach will be exemplified for a model oxidative electrosynthesis reaction and the individual elements of the platform will be discussed.

References

[1] R.F. Service, Renewable bonds, Science, 365 (2019) 1236-1239.
[2] K.M. Van Geem, V.V. Galvita, G.B. Marin, Making chemicals with electricity, Science, 364 (2019) 734-735.
[3] P. Khanipour, M. Löffler, A.M. Reichert, F.T. Haase, K.J.J. Mayrhofer, I. Katsounaros, Electrochemical Real-Time Mass Spectrometry (EC-RTMS): Monitoring Electrochemical Reaction Products in Real Time, Angew. Chem. Int. Ed., 58 (2019) 7273-7277.
Highly Selective and Scalable Electrolysis for Gaseous CO2 Reduction in the Zero-Gap Electrolyzer
Authors: Lee Woong Hee , Hwang Yun Jeong , Min Byoung Koun , Oh Hyung-Suk 
Published: May 2020

The electroreduction of carbon dioxide (CO2) to chemicals represents a promising pathway for the storage of renewable electricity and toward low-carbon-footprint chemicals production. Prior study on CO2RR have focused on the catalytic properties of various materials in liquid condition. However, the current density for CO2RR is restricted under 30 mA cm–2 due to the mass transfer limit and low solubility of CO2 in the aqueous solution. To increase the current density, the gas fed CO2 electrolysis system was investigated using a gas-diffusion layer (GDL) system. Masel et al. reported about new zero-gap CO2 electrolysis device that uses an anion exchange membrane (AEM, SustainionTM) with humidified CO2 flow in the cathode and shows a current density of 200 mA cm-2 with steady FECO of over 90% using Ag catalyst.
Herein, we developed a convenient Ag-based and Cu-based electrode with high selectivity and high current density for electrochemical conversion of CO2 to CO and ethylene in a zero-gap electrolyzer, respectively. We tested the electrochemical properties of the prepared Ag-based electrode in the gaseous CO2-fed electrolyzer and H-type electrochemical cell with respect to CO2RR. Ag coral electrode achieves CO partial current density of 312 mA cm–2 with FECO > 95%. Cu-KOH electrode demonstrate 260 mA cm–2 current density with 60.5 % C2H4 faraday efficiency at 10 cm2 electrode area. Moreover, the prepared electrode was analyzed the change of electronic structure using in-situ/operando X-ray absorption spectroscopy (XAFS) at real gas fed zero-gap electrolyzer condition. Based on these results, we could give insights about the scalable electrolyzer system for electrochemical conversion of CO2 with high catalytic activity and selectivity.
Engineered Electrolyte-Electrocatalyst Nanocomposites for Enhanced CO2 Electroreduction
Authors: Elgammal Ramez A. , Zawodzinski Thomas A. 
Published: May 2020

The development of a viable approach to capture, store, and convert carbon dioxide into fuels and chemicals may offer a means to mitigate climate change while also creating value added commodity chemicals. Critical bottlenecks in existing technologies that have impeded commercialization of CO2 electrosynthesis include catalysts with high overpotentials and limited selectivities. Furthermore, current approaches often employ PEM-based electrolyzers that suffer from low CO2 solubility in acidic aqueous solutions, limiting mass transport and reaction rates, or AEM-based systems which have much higher CO2 solubilites in alkaline electrolytes, but have the added problem of membrane poisoning by bicarbonate and carbonate.
We have recently developed an electrochemical reactor that overcomes many of the shortcomings that have limited the above technologies. Our preliminary results suggest that onset potentials for CO2 reduction are more than 200 mV lower than with current densities in excess of 150 mA/cm2 at -1 V vs RHE. The selectivities for CO are in excess of 90% and the electrocatalysts. We have examined several cathode electrocatalysts and some of the most promising include a series of nanostructured mixed and/or doped transition metal and main group metal oxides that also suppress the hydrogen evolution reaction. We will present detailed electrochemical and structural studies and will comment on possible reaction mechanisms as well as the key features of the reactor that enable the enhanced kinetics.
Techno-Economic Perspectives on Upgrading Carbon Dioxide into Higher-Value Chemicals
Authors: Pritchard Tyler Lynn , Sullivan Neal P , Braun Robert J. 
Published: May 2020

We present our early stage techno-economic analyses on electrochemical upgrading of sequestered carbon dioxide into higher-value chemicals. The technology seeks harness intermittent, renewable electricity to drive electrochemical processes that convert CO2 into fuels. Through our techno-economic study, we explore the cost functions and value propositions of this energy-storage technology.
With the deployment of intermittent renewable energy resources into the utilities sector, research into fast and efficient forms of energy storage has become critical to address the temporal variation associated with these renewable resources. Our efforts seek to convert this renewable-but-intermittent electricity into chemical energy that is more-easily stored. This power-to-chemicals conversion utilizes water vapor and carbon dioxide feedstocks to form methane and higher-value chemicals. The approach has the potential to decrease CO2 emissions while providing storage for intermittent renewables.
The renewable electricity is used to drive solid-oxide electrolysis cells that feature novel proton-conducting ceramics. As shown in the figure, the protonic-ceramic electrolyzers split the water-vapor feedstock at the steam electrode into protons and molecular oxygen. The protons (H+) are transported across the dense protonic-ceramic membrane to the fuel electrode, while the molecular oxygen simply exhausts from the electrolyzer. At the fuel electrode, the protons serve to hydrogenate the CO2 into higher-value chemicals, such as methane. If successful, such a device could be harnessed to convert renewable electricity into a drop-in fuel for our nation’s natural gas infrastructure.
We are developing a techno-economic analysis (TEA) of an protonic-ceramic electrolysis cells (PCECs) to determine the value proposition of CO2-to-methane synthesis,. Our TEA draws from previously established models of more-common solid-oxide electrolysis cells (SOECs). To date, our TEA was built around a single-cell PCEC model in MATLAB that was later migrated to Aspen HYSYS for integration with larger thermofluid systems. The preliminary MATLAB model utilized a straightforward current-density-dependent voltage model for the SOEC, similar to the equation commonly used to model SOFCs. The TEA looked specifically at the cost associated with production of methane from a PCEC sized to consume three tons of coal feedstock CO2 equivalent per day.
Projected costs vary with the assumed performance point: peak flow efficiency, peak stoichiometric efficiency, or peak methane production rate. Continued iterations of this model will lend more insight into how these cost projections change with scale, and provide insight on cost drivers.

Figure 1