bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) An Electrolyte Odyssey with Bob Savinell
Authors: Zawodzinski Thomas A. 
Published: November 2022

Over approximately 30 years, I have enjoyed interweaving my career with interactions with Bob Savinell. After some initial remarks on that ‘odyssey’ (or is it oddity?), I will discuss recent research in two pathways in which we overlapped: (i) an indirect one devoted to finding fuel cell membranes and systems that operate at temperatures above 100oC; and (ii) our direct interactions on the BEES EFRC.
Of course, the Savinell group proposed an elegant solution to that with the PBI-PA based fuel cell membrane and that has substantial system advantages for certain modes of operation. However, more mainstream PEM fuel cell membranes operating at T >100oC and with relatively little water continue to be sought. These are of considerable import because of the possibility that a car or truck will experience temperature excursions in that range. I will summarize the current state of the art of that field and discuss work in our lab that attempts to provide some solutions. I will also discuss our group’s work with a variant, the Solid Acid Fuel Cell, showing some progress achieved toward dramatic decreases in catalyst loading for a fuel cell that operates at roughly 250oC;.
In BEES, our group has worked on several issues (see other presentations in this symposium and meeting) but much of the focus has been on microemulsions as electrolytes, particularly in the context of redox flow batteries. I will present a brief overview of that work as the most direct and recent example of our collaborations.
(Invited) HT-PEMFC Based on Acid Doped Polybenzimidazoles of the Past Quarter Century
Authors: Hjuler Hans , Li Qingfeng , Aili David , Jensen Jens Oluf Oluf , Cleemann Lars N. , Azizi Kobra , Seselj Nedjeljko 
Published: November 2022

High-temperature proton exchange membrane (HT-PEM) fuel cells based on phosphoric acid-doped polybenzimidazole (PBI) membranes were invented in 1994 by professor Bob Savinell and his coworkers at Case Western Reserve University [1]. The membrane electrolyte is a unique material that is capable of practical proton conductivity at temperatures of up to 200oC under anhydrous conditions. This ground-breaking invention has led to the start of a frontier research area for fuel cells and related technologies, as indicated by an annual publication of ca. 200 items and citation of 10,000 times in the last decade.
Based on this type of membrane materials, the HT-PEM technology has developed, with operating features including little humidification, high CO tolerance, easy thermal management and thermal integration with methanol reformer.[2] Significant efforts from international industries are currently made towards commercialization and products are now on the market. Research institutions and industries in Denmark have been active and leading in the research and development of the area. Further, the PBI membrane has also emerged as a promising membrane material for redox flow batteries (RFB).
This presentation is devoted to a brief summary of the fundamental understanding and technological deployment of this technology [3], as a remark of the extraordinary contributions of Professor Savinell to the electrochemistry and electrochemical engineering research.
References
[1] J.S. Wainright JS, J.T. Wang, D. Weng D, R.F. Savinell, M. Litt. Acid-doped polybenzimidazoles—a new polymer electrolyte. J Electrochem Soc 1995;142:L121–3.
[2] Q.F. Li, D. Aili, H. A. Hjuler, J.O. Jensen, High Temperature Polymer Electrolyte Membrane Fuel Cells - Approaches, Status and Perspective, ISBN 978-3-319-17081-7; Springer International Publishing, New York, 2015.
[3] D. Aili, D. Henkensmeier, S. Martin, B. Singh, Y. Hu, J. O. Jensen, L. N. Cleemann, Q.F. Li, Polybenzimidazole-Based High-Temperature Polymer Electrolyte Membrane Fuel Cells: New Insights and Recent Progress, Electrochemical Energy Reviews (2020) 3:793–845
(Digital Presentation) Fundamentals of Deep Eutectic Solvents As Electrolytes for Lithium-Ion Batteries
Authors: Elgammal Ramez A. , Fraenza Carla Cecilia , Greenbaum Steven , Zawodzinski Thomas A. 
Published: November 2022

Deep eutectic solvents (DESs) have emerged as an alternative to both common organic solvents and ionic liquids (ILs). DESs share physicochemical properties with ILs such as low vapor pressure, high thermal stability, high viscosity while offering advantages such as low toxicity, lower cost, and ease of preparation. Moreover, DESs are attractive candidates for electrochemical applications due to their large voltage windows and solubility properties. DESs as a solvent class share a general composition of a hydrogen bond donor (HBD), typically a polyol, amide, or acid, and a hydrogen box acceptor (HBA), usually a quaternary ammonium or phosphonium salt. At a specific molar composition of a HBD and HBD, the DES forms a eutectic mixture resulting in a large melting point depression due to extensive hydrogen bonding between the components.
Despite being widely studied, the microscopic structures of DESs have remained largely uncharacterized. Herein, we present a multitechnique NMR study of two DESs: glyceline (glycerol + choline chloride) and ethaline (ethylene glycol + choline chloride). Fast-field cycling 1H relaxometry, pulsed field gradient diffusion, nuclear Overhauser effect spectroscopy (NOESY), 13C NMR relaxation, and pressure-dependent NMR experiments are deployed to sample a range of frequencies and modes of motion of the polyol and choline components of the DES. Generally, translational and rotational diffusion of polyols are more rapid than those of choline while short-range rotational motions observed from 13C relaxation indicate slow local motion of glycerol at low choline chloride (ChCl) content. We show how the additional hydroxyl group present in glycerol contributes to not only higher viscosities, but a larger perturbation of the hydrogen bonding network by the addition of ChCl.
Additionally, we have investigated the solubility properties of several lithium salts (LiTFSI, LiFSI, LiPF6, LiBF4, and LiOAc) in these DESs and utilized the same suite of NMR techniques to understand how they act as solvents. We observe that due to anion effects, the heterogeneities present in DES result in differential solvation for some species where there is a distinction of lithium salts co-existing in these holes as well as the bulk. The large changes in the structural organization of DESs that result from the presence of lithium salts will serve as a guide to the design of a new class of electrolytes for lithium-ion batteries.
(Invited) Interfacial Engineering of Battery Materials Using Atomic Layer Deposition
Authors: Dasgupta Neil P. 
Published: November 2022

In batteries, like all electrochemical systems, interfacial phenomena play a critical role in thermodynamic stability, charge transfer kinetics, and ionic transport phenomena. For example, in Li-ion batteries, the solid-electrolyte interphase (SEI) layer enables stabilization of liquid electrolytes against continual electrolyte decomposition. In solid-state batteries, the dynamic morphological evolution of the interface results in unique electro-chemo-mechanical properties, which dictate performance, degradation, and ultimate failure.
As a result of these coupled phenomena, there is a continued need to improve both our fundamental understanding of interfacial dynamics, as well as new strategies to engineer rationally-controlled interfaces. Among the various interfacial engineering methodologies, atomic layer deposition (ALD) has risen in interest in recent years, owing to its unparalleled ability to impart atomically-precise control of surface composition and structure, while maintaining conformal coating of ultra-high aspect ratio structures.
In this talk, I will describe recent progress in applying ALD for battery applications. In the field of Li-ion batteries, I will show how deposition of a single-ion conducting solid electrolyte on the surface of graphite anodes can eliminate electrolyte decomposition and SEI formation, resulting in a four-fold decrease in interfacial resistance [1]. This results in lower cell polarization during fast charging, eliminating deleterious Li plating on the anode. In the field of Li metal batteries, I will also show how ALD coatings can influence nucleation and growth, resulting in improved Coulombic efficiency [2]. Finally, I will describe efforts towards incorporation of ALD films into solid-state batteries, where mechanical properties play a critical role [3-4].
[1] E. Kazyak, K.-H. Chen, Y. Chen, T. H. Cho, N. P. Dasgupta, Adv. Energy Mater.
12, 2102618 (2022).
[2] K.-H. Chen, A. J. Sanchez, E. Kazyak, A. L. Davis, N. P. Dasgupta, Adv. Energy Mater.
9, 1802534 (2019).
[3] A. L. Davis, R. Garcia-Mendez, K. N. Wood, E. Kazyak, K.-H. Chen, G. Teeter, J. Sakamoto, N. P. Dasgupta,
J. Mater. Chem. A
8, 6291 (2020)
[4] E. Kazyak, M. Shin, W. S. LePage, T. H. Cho, N. P. Dasgupta,
Chem. Commun.
56, 15537 (2020).
(Invited) Effects of the Alloy Composition on Cycling Performance of Cu-Ni Alloy Cathodes in All-Solid-State-Fluoride-Shuttle Batteries
Authors: Motoyama Munekazu , Sakurai Katsutoshi , Kiuchi Hisao , Nakatani Tomotaka , Nakagawa Takashi , Iriyama Yasutoshi , Ogumi Zempachi , Abe Takeshi 
Published: November 2022

Metal fluorides generally have low electric conductivities. Hence, if a single metal (e.g. Cu) is used as the cathode active material for a fluoride-shuttle battery (FSB), the electric resistance in the cathode increases after the fluoridation reaction (charging).1,2 Hence, repeating charging and discharging leads to significant drop in capacity. If an alloy consisting of two metal elements with different fluorination/defluorination potentials is used as the cathode active material, one metal element behaves as a conductive metal even when the other metal element is fluorinated, and the increase in electric resistance can be suppressed. So, we evaluated Cu-Ni binary alloys as cathode active materials for FSB in this study.
The standard redox potentials (25 °C) of NiF2/Ni and CuF2/Cu are +0.11 V and +0.72 V (vs. PbF2/Pb), respectively. 3 Although NiF2 is an insulating compound, Cu behaves as a metal, providing electron conduction pathways. Additionally, the crystal structures of Cu and Ni are commonly fcc structures, with lattice constants of 3.597 Å and 3.499 Å, respectively, so that Cu-Ni alloys exhibit solid solutions in the full composition range above 380 °C in the phase diagram. Hence, the Cu-Ni alloy is considered to be an ideal alloy system that hardly separates different phases and can provide highly-dense-interconnecting-electron-conduction pathways within the whole cathode like veins.
Cu
x
Ni1−x
(x = 0, 0.3, 0.5, 0.7, 1.0) films with thicknesses of approximately 3 nm were sputter-deposited onto 0.5-mm-thick LaF3 solid electrolytes to form all-solid-state PbF2/LaF3/Cu
x
Ni1−x
cells. Charging/discharging curves and Nyquist plots of the cells were measured under high vacuum (< 10−3 Pa) at 140 °C.

Acknowledgment

This paper is based on the results obtained from projects, JPNP16001 and JPNP21006, commissioned by the New Energy and Industrial Technology Development Organization (NEDO).

References

Okazaki et al., ACS Energy Lett.,
2, 1460 (2017).

Yamamoto et al.,
ACS Appl. Energy Mater.
,
2, 6153 (2019).

Gschwind et al., J. Fluor. Chem., 182, 76 (2016).
(Invited) Effects of Support Mesoporosity on Pt Dissolution in PEM Fuel Cells
Authors: Atwa Marwa , Goh Timothy , Dull Samuel , Prinz Fritz 
Published: November 2022

Interest in hydrogen as an energy carrier continues to grow due to the high demand for clean and sustainable, energy sources in the global energy market. Polymer exchange membrane fuel cells (PEMFCs) convert the chemical energy of hydrogen to electricity and have great potential as power sources for automotive applications. A key challenge in the development of cost-efficient and reliable PEMFC electrodes is catalyst layer durability. Typically, PEMFC cathodes comprise Pt-based electrocatalysts supported on high-surface-area carbons. It has been previously shown that the morphology and surface chemistry of carbon supports play significant roles in modulating both the activity and stability of Pt-based catalysts.
Here, we will present our recent efforts to investigate the effects of the porous structures and surface properties of different mesoporous carbon powders on Pt dissolution in PEMFC cathodes. Using atomic layer deposition (ALD), we fabricate cathodes by depositing Pt nanoparticles of uniform sizes and mass loadings onto mesoporous carbon supports with varying pore sizes and surface areas. We then evaluate the beginning-of-life and end-of-life performance of these cathodes after accelerated Pt dissolution tests under single cell conditions, while comparing them to a microporous Ketjenblack-based cathode as a benchmark. Based on our findings, we discuss new insights into the underlying mechanisms for Pt dissolution within the porous structures of mesoporous carbon supports.
(Invited) Enhancing Fuel Electrode Reliability of Solid Oxide Electrolyzers
Authors: Elangovan S , Hafen Tyler , Rane Taylor , Pike Jenna , Larsen Dennis , Hartvigsen Joseph 
Published: November 2022

Solid oxide electrolysis (SOXE) provides a high efficiency pathway to electrolyze steam, carbon dioxide, or a mixture of the two to produce hydrogen, carbon monoxide, or synthesis gas respectively. Irrespective of the cell design, instability of fuel electrode is a source of performance degradation.
Traditionally, solid oxide electrolysis stacks use nickel–zirconia or nickel–ceria composite cathode to reduce the oxidized species. Nickel based electrodes are susceptible to oxidation by the feed gas (CO2 or steam) at the inlet conditions and are often irreversibly damaged unless reducing gas (carbon monoxide or hydrogen) is also present. This necessitates a complex, recycle loop that introduces a fraction of the product gas to the inlet. The gas recycle approach was successfully implemented for OxEon’s SOXE stack that is operating on Mars to produce high purity oxygen using atmospheric carbon dioxide. Under a NASA SBIR program, OxEon investigated a combination of materials and engineering solutions to improve redox tolerance of the nickel based cathode so that 100% dry CO2could be fed directly into a stack without damaging the electrode. The redox tolerance through the use of a modified nickel based cathode composition has been demonstrated. Button cells and stacks have been shown to tolerate complete oxidation of Ni to NiO, with performance recovery occurring in a matter of minutes using only the CO generated by the electrolysis reaction to re-reduce the cathode. The redox tolerant stack was also demonstrated to show improved coking tolerance over the traditional cathode material. This feature allows higher conversion of CO2enabling increased O2 production. Tests are ongoing to evaluate redox tolerance for steam electrolysis.
Methanol Fueled Low Temperature Solid Oxide Fuel Cell with Pt-SDC Anodes
Authors: Yang Byung Chan , Jo Sung Eun , Kim Taeyoung , Park Geonwoo , GO Dohyun , Gur Turgut M. , An Jihwan 
Published: November 2022

A low-temperature solid oxide fuel cell (LT-SOFC) is a next-generation energy conversion device and has advantages of high energy efficiency, fast start up and shut down and eco-friendliness. In addition, since it has the advantage of being able to use various fuels such as hydrogen, alcohol, and methane gas, research is being actively conducted in recent years. However, LT-SOFC using hydrogen as a fuel has difficulties in storing and transporting fuel, making it difficult to apply as a portable device. On the other hand, methanol fuel is an attractive alternative fuel because it is easier to transport and store than hydrogen fuel and has a high volumetric energy density. However, when methanol is applied to LT-SOFC, there is a disadvantage in performance due to the complicated oxidation process and CO poisoning. Complex methanol oxidation reaction (MOR) and CO poisoning reduce the performance and durability of fuel cells. Therefore, it is important to use a catalyst that can prevent CO poisoning and improve the oxidation reaction of methanol. Pt is an effective catalyst for methanol decomposition and is one of the materials widely used in direct methanol fuel cell (DMFC). However, there is a problem in that it is vulnerable to CO generated during the methanol oxidation process. It is known that CO is adsorbed on the Pt surface, blocks the active site, and reduces catalytic activity. Therefore, alloying Pt with samaria-doped ceria (SDC) with high oxygen storage capacity (OSC) and good OH generation capacity can be effective to reduce CO poisoning and coking.
In this study, we prepared the cells with Pt-SDC cermet anodes with the Pt volume percent of 69 (Pt 0.69), 83 (Pt 0.83), 92 (Pt 0.92), and 95 (Pt 0.95) volume% by varying Pt and SDC powers in the co-sputtering process. In the electrochemical impedance spectroscopy (EIS), ohmic resistance was similar between all samples; on the other hand, activation resistance was measured to be 24.0, 19.5, 31.8, 30.8, and 53.0 Ω∙cm2 at Pt 0.69, Pt 0.83, Pt 0.92, Pt 0.95, and Pt 1 samples, respectively, confirming the lowest activation resistance at Pt 0.83. We speculate that the MOR is improved by the increase of triple phase boundary (TPB) sites and the facilitation of bifunctional CO oxidation mechanisms with higher content of SDC up to 17 mol% (Pt 0.83). However, in the anode with excessive SDC content (31 mol%, Pt 0.69), the Pt is oxidized to form PtO2, lowering the catalytic activity.
Highly Durable Solid Oxide Fuel Cells: Prevention of Chemical Inter-Diffusion By Introducing a 4-Layered Structure
Authors: Hussain Amjad , Song Rak-Hyun , KIM TAE-Hun , Kwon Beom-Su , Ali Muhammad Measam , Joh Dong Woo , Hong Jong-Eun , Lee Seung-Bok , Lim Tak-Hyoung 
Published: November 2022

Solid oxide fuel cell (SOFC) poses great potential for stationary power generation. Nevertheless, its full-scale commercialization has lagged due to the inadequacy of long-term durability. Along with diverse background of performance deterioration, the inter-diffusion between the cathode and electrolyte have been identified as a leading fatal factor. Herein, we introduced a robust GDC layer by sequential lamination approach that completely suppresses the detrimental phase of SrZrO3 at electrolyte interface during high temperature operation. This buffer layer is fabricated via green film sequential lamination, in which the anode support, anode functional layer, electrolyte and GDC layers were sequentially co-laminated by iso-static pressing and co-sintered at 1300-1400°C. The enhanced interfacial connectivity and desired packing density of electrolyte and buffer layer were attained by controlling the shrinkages behaviors of each component. Thus, the formation of detrimental secondary phases (SrZrO3) at interface of electrolyte and decomposition of cathode are successfully restrained during fabrication and operation at critical current density. The scale-able and mass production are also confirmed through the fabrication of large area cells (144cm2) having active area 100cm2. The sequentially co-laminated GDC layer exhibited extreme low degradation rate of 0.2%/khr, which fulfils the critical longevity benchmark for commercialization of technology. This work features a cost-effective, scalable, and reproducible method for larger scale production of robust multi-layer anode supported SOFC.
Keywords: Durability, Sequential lamination, life expectancy, Detrimental phases, iso-static pressing
Doped Barium Niobate Perovskite Based Materials for High-Temperature Electrolyzer Application and Efficient Methane Conversion
Authors: Ramaiyan Kannan , Denoyer Luke H , Benavidez Angelica , Garzon Fernando H. 
Published: November 2022

Perovskite materials have helped make notable advances in many applications over the last few decades. Specifically, in high temperature electrochemical technologies such as solid oxide fuel cells (SOFC) and electrolyzers where perovskite-based electrolyte and electrode materials are playing pivotal roles. However, high temperature operation poses significant challenges in both fabrication and durable operation that is further complicated by the operating environment. For example, an electrolyte in a SOFC faces a highly oxidizing environment on the cathode while highly reducing environment on the anode and hence should possess chemical stability under these operating conditions and lifetime requirements for energy conversion technologies often times exceed 10 years of usage with no more than 20% degradation.[1]. Electrochemical oxidative coupling of methane (E-OCM) to ethylene process faces further problems associated with coke and carbonate formation along with the over oxidation of CH4 that invariably leads to CO and CO2. Here we present exciting class of barium niobate perovskites where different cations such as Mg, Ca, Y, and Fe on the niobium site was used for doping and evaluated for E-OCM application. The results are compared with another perovskite material Sr2Fe1.5Mo0.5O6-
d (SFMO) that showed good catalytic activity but poor chemical stability. [2][3] Prepared perovskite material was analyzed by XPS, TGA, TPR, SEM, and TEM methodologies towards their chemical stability. Electrochemical properties were evaluated in a home-made setup using different electrolyte materials in the temperature range of 700°C to 900°C by methods such as cyclic voltammetry, impedance spectroscopy, and chronoamperometry. Electrochemical measurements coupled with continuous mass spectra analysis provided valuable insights between product distribution and applied potential. Our results demonstrate doped barium niobates as a promising candidate for stable operation in high temperature electrochemical applications.

References

[1] A. Hauch, S. D. Ebbesen, S. H. Jensen, and M. Mogensen, “Highly efficient high temperature electrolysis,” J. Mater. Chem., vol. 18, no. 20, pp. 2331–2340, 2008, doi: 10.1039/B718822F.
[2] K. P. Ramaiyan, L. H. Denoyer, A. Benavidez, and F. H. Garzon, “Selective electrochemical oxidative coupling of methane mediated by Sr2Fe1.5Mo0.5O6-δ and its chemical stability,” Commun. Chem., vol. 4, no. 1, p. 139, 2021, doi: 10.1038/s42004-021-00568-1.
[3] C. Zhu, S. Hou, X. Hu, J. Lu, F. Chen, and K. Xie, “Electrochemical conversion of methane to ethylene in a solid oxide electrolyzer,” Nat. Commun., vol. 10, no. 1, p. 1173, 2019, doi: 10.1038/s41467-019-09083-3.
(Invited) Selenium as a Top-Cell Absorber Candidate for Tandem Photoelectrochemical Stacks
Authors: Nielsen Rasmus , Youngman Tomas , Crovetto Andrea , Seger Brian , Hansen Ole , Mustafa Hadeel , Levcenco Sergiu , Hempel Hannes , Olsen Thomas , Chorkendorff Ib , Unold Thomas , Vesborg Peter 
Published: November 2022

The ideal high-bandgap partner for a tandem solar absorber using c-Si as the low-bandgap bottom cell must have a bandgap of around 1.9 eV and excellent optoelectronic properties.
Selenium, perhaps the very first material to be studied for its photovoltaic properties, is emerging as an interesting candidate for this application. Indeed Se has a bandgap of around 1.95 eV [1] and a steep increase in absorption above this photon energy. Todorov et al showed [2] in 2017 that single-junction Se solar cells could reach 6.5% efficiency using a new cell architecture with a very thin absorber layer. Recently we have increased the OCV to a new record of 991 mV [2]. Simultaneously, we are also starting to identify the main shortfalls of state-of-the-art Se films which so far have prevented Se-cells from approaching their theoretical potential OCV, which is of course much higher than 991 mV. The talk will introduce Se as a solar absorber and discuss we know about its properties and use in solar devices such as PEC stacks.
[1] T. K. Todorov, S. Singh, D. M. Bishop, O. Gunawan, Y. S. Lee, T. S. Gershon, K. W. Brew, P. D. Antunez and R. Haight, Nature Communications, 2017, 8, 682
[2] R. Nielsen, T. Youngman, H. Moustafa, S. Levcenco, H. Hempel, A. Crovetto, T. Olsen, O. Hansen, I. Chorkendorff, T. Unold, P. C. K. Vesborg, (in preparation), 2022