bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Ce(Mn,Fe)O2/La(Sr)Fe(Mn)O3 Nano Size Film As a Dense Anode for Low Temperature Solid Oxide Fuel Cells
Authors: Ishihara Tatsumi , Yoshikai Masaru , Ju Young Wan , Ida Shintaro 
Published: February 2020

Solid oxide fuel cells (SOFCs) have been attracting much interest as alternative and efficient energy conversion system for next generation. Ni–yttria stabilized zirconia (YSZ) cermets anode film was prepared with laser ablation method. However, large volumetric changes of cermets film and Ni agglomeration cause micro-crack and delaminating thin film in reducing atmosphere. Therefore, investigations for thin film anode have been hardly progressed up to now. We studied dense La(Sr)Fe(Mn)O3-δ (La0.6Sr0.4Fe0.9Mn0.1O3-δ, LSFM) thin ceramic film as an dense anode concept for expanding reaction site from three phase boundary (anode–electrolyte–gas) to two phase one (anode–gas phase) by PLD process. In our previous work, metallic substrate was studied as the porous anode in IT-SOFC. The Ni–Fe substrate exhibited excellent tolerance against thermal-/redox- cycling. Furthermore, the cell using Ni–Fe anodic metal substrate exhibited fairly high power density at intermediate temperature. However, the power density of metal-supported cell was slightly lower than that of cermets-supported cell in our previous study because of limited number of three phase boundary. In order to achieve high power density and stability of intermediate temperature solid oxide fuel cells (IT-SOFC), Ce(Mn,Fe)O2(CMF)-La(Sr)Fe(Mn)O3-δ (LSFM) dense nano-film anode is introduced between Ni–Fe metallic substrate and LaGaO3 base oxide electrolyte. Although it is believed that three phase boundary (TPB) is essentially required for anode active site, the cell using CMF-LSFM mixed conducting thin film anode exhibits reasonable power density comparing with that of the cell with a simple porous Ni–Fe anode, however, slightly decreased comparing with that of LSFM single layer. The maximum power density of the cell having CMF-LSFM film is approximately 2.0 W/cm2 at 973 K. On the other hand, application of double columnar composite of CMF/LSFM shows much smaller anodic overpotential and higher power density at intermediate temperature. Therefore, this study reported the dense film of CMF and LSFM with few 100 nm thickness can be used as dense anode.
Protonic Ceramic Fuel Cell Stacks
Authors: Ding Hanping , Duan Chuancheng , Tong Jianhua , Le Long , Ricote Sandrine , O'Hayre Ryan , Sullivan Neal P 
Published: February 2020

In this report, we present our work on development of fuel cell stacks based on proton-conducting ceramic materials. Such protonic-ceramics have demonstrated great promise for addressing the technological challenges now facing the solid-oxide fuel cell community. Protonic ceramic fuel cells (PCFCs) based on BaCe0.7Zr0.1Y0.1Yb0.1O3-δ have demonstrated high power density at low operating temperatures, achieving 450 mW / cm2 at 500 ºC under hydrogen fuel [1, 2]. PCFCs may also be more amenable to internal reforming of hydrocarbon fuels (CH4 + H2O => 3 H2 + CO). Proton conduction removes H2from the anode stream, thereby shifting the internal-reforming equilibrium chemistry towards the products, promoting higher methane conversion. While these materials show great promise, no multi-cell PCFC stacks have been fabricated to date.
In this presentation, we review our progress in extending previous single “button-cell” experiments to small fuel-cell stacks. The stack design is shown in Figure 1; PCFC membrane-electrode assemblies (MEAs) are bonded within a ceramic frame, and the frame is packaged within ferritic-steel interconnects. Fabrication of MEAs involves solid-state reactive sintering (SSRS), where the protonic-ceramic fuel cell material is formed from simple parent oxides during co-sintering of the anode-electrolyte assembly. This single-step fabrication greatly reduces MEA-manufacturing costs and improves yields.
Multi-cell stack prototypes have been demonstrated. A three-cell stack based on BaCe0.2Zr0.6Y0.2O3-δ electrolyte shows open-circuit voltage that approaches the theoretical Nernst potential (Figure 1), and demonstrates excellent stability over 500 hours of continuous operation. The stack also yields reasonable power density, reaching 250 mW/cm2at 650 ºC. Moving forward, higher performance is expected as we improve fabrication and packaging methods.
Citations:
[1] C. Duan, J. Tong, M. Shang, S. Nikodemski, M. Sanders, S. Ricote, A. Almansoori, R.P, O’Hayre, “Readily processed protonic ceramic fuel cells with high performance at low temperatures,” Science
349: 6254 (2015) 1321-1326.
[2] J. Kim, S. Sengodan, G. Kwon, D. Ding, J. Shin, M. Liu, G. Kim, “Triple-conducting layered perovskites as cathode materials for proton-conducting solid oxide fuel cells,” ChemSusChem
7(2014) 2811–2815.

Figure 1
Characterization and Performance of Proton Conducting Solid Oxide Fuel Cells Manufactured Using Reactive Spray Deposition Technology
Authors: Myles Timothy D. , Ouimet Ryan , Kwak Dongwook , Maric Radenka 
Published: February 2020

Proton conducting solid oxide fuel cells (p-SOFC) have received attention recently as an alternative to traditional high temperature SOFCs [1]. This new class of p-SOFCs offer the potential to significantly reduce the cost of production due to the opportunity to lower the operating temperature from upwards of 800 °C down to as low as 500 °C. This shift is made possible by a modified class of ion conducting materials such as yttrium doped barium zirconate (BYZ) which has comparable ionic conductivity to yttria-stabilized zirconia at lower temperatures [2]. With a decrease in the operating temperature, it becomes possible to make use of inexpensive materials for cell construction such as stainless steels vs. expensive super alloys. This cost savings is a major driver towards practical commercialization of p-SOFCs. This work seeks to employ a novel flame based technique, Reactive Spray Deposition Technology (RSDT) [3], in manufacturing of a complete p-SOFC on a metal support. This technique involves dissolving organometallic precursor compounds (typically ethlyhexanoate ligands) into combustible solvents. The mixture is sprayed from an atomizing nozzle in an open atmosphere and ignited. The resulting heat of combustion due to the solvent is used to decompose the dissolved compounds and produce thin films via gas to particle conversion. The use of the flame eliminates the need for separate, costly sintering steps generally needed in traditional manufacturing processes. Secondary nozzles can be utilized to introduce different support and binder materials resulting in a single-step manufacturing process for the anode, electrolyte, and cathode of the p-SOFC. The current work focuses on the production and initial characterization of a p-SOFC using a Ni-BYZ anode, BYZ electrolyte, and lanthanum strontium cobalt ferrite (LSCF) cathode on a porous metal support. The deposited materials are characterized using SEM, STEM, and XRD techniques. Initial button cell performance is also reported.
References:
[1] F. Lefebvre-Joud and G. Gauthier, and J. Mougin, J. Appl. Electrochem., 39 (2009) 535-543.
[2] Y. Yoshihiro, R. Hernandez-Sanchez, and S. M. Haile, Chem. Mater., 21 (2009) 2755-2762.
[3] R. Maric, J. Roller, and R. Neagu, J. Therm. Spray Techn., 20 (2011) 696-718.
(Invited) Enhanced Electrochemical Activites in Perovskite Oxides through Strain Control of the Oxygen Stoichiometry
Authors: Lee Ho Nyung 
Published: February 2020

Functional ionic defects, such as oxygen vacancies, in perovskite oxides facilitate catalysis critical for energy storage and conversion devices. However, the deliberate control of oxygen stoichiometry in perovskite-based oxides is challenging due to difficulties in activating these functional oxygen defects at the reduced temperatures required for the low temperature operation of energy storage and generation devices, such as batteries and fuel cells. Here, we use strontium cobaltite (SrCoOx) “oxygen sponge” to show that epitaxial strain is a powerful tool towards controlling the oxygen vacancy concentration even in highly oxidizing environments, including conditions during the oxygen evolution reaction (OER) that otherwise fully oxidize unstrained SrCoOx. Our computational approach found that the thermodynamic barrier towards oxygen activation could be lowered by applying a small biaxial tensile strain (~30% with 2% strain). The corresponding change was also experimentally observed, yielding an increasingly oxygen deficient state. The additional oxygen vacancies created by strain artificially enhance the cobaltites’s catalytic activity towards the OER by over an order of magnitude. Our findings demonstrate that strain, rather than simply relying on ambient conditions, can act as the key tuning parameter of oxygen stoichiometry in the next generation of catalytic oxides, functionalizing vacancies for realizing low temperature energy applications.
* This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division (synthesis, theory, and optical and physical property characterization) and by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy (electrochemical characterization).
(Invited) Electrospun Particle/Polymer Fiber Mats As Fuel Cell and Battery Electrodes
Authors: Pintauro Peter N. 
Published: February 2020

Electrospinning is gaining popularity as a convenient and robust technique for fabricating non-woven mats of sub-micron diameter polymer fibers. Although not as well studied, the technique can also be used to prepare particle/polymer fiber networks with high intra- and inter-fiber porosity. Such fibrous networks can be used as porous electrodes in fuel cells and batteries, where high interfacial electrode area, i.e., the accessibility of electrode material within a 3-D anode or cathode architecture, is of prime importance. In this talk, a review of recent experimental work on nanofiber mat architectures for hydrogen/air fuel cell cathodes and lithium battery anodes and cathodes will be presented, where the particle loading in the fibers is very high. The fuel cell work is focused on fibers containing carbon supported Pt or Pt-alloy powders with various perfluorosulfonic acid polymer based catalyst binders. The fuel cell power output using such a cathode is very high for ultra-low Pt loadings. Additionally, carbon corrosion of nanofiber cathodes, as determined from voltage cycling experiments, can be minimized by proper adjustment of the hydrophilic/hydrophobic properties of the catalyst binder. For Li battery applications, nanofiber anodes have been prepared and evaluated, where the fibers are composed of either TiO2 and carbon powders with poly(acrylic acid) binder or carbon powder and poly(vinylidene fluoride) (PVDF). Here, the volumetric capacity of a fiber anode at charge/discharge rates of 1C-3C are considerably higher than those measured with a conventional slurry anode. Electrospinning can also be used to prepare ultra-thick anodes with high areal capacities, e.g., 2.5 and 1.3 mAh/cm2 at charge/discharge rates of 1C and 2C, respectively. Similarly, Li battery nanofiber cathodes with LiCoO2 and carbon powders in a PVDF binder have been fabricated and evaluated at various areal capacities and C-rates. Experimental details for both fuel cell and battery electrodes will be presented in this talk, including the procedures for electrospinning fibers, the methods for characterizing the fiber mats, and the properties and performance of the particle/polymer mats in a given application.
Effective Nickel and Ruthenium Modified Palladium Anode Catalysts for Ethylene Glycol Oxidation in Alkaline Medium
Authors: Da Silva Rodrigo Garcia , De Andrade Adalgisa Rodrigues , Servat Karine , Morais Claudia , Napporn Teko W. , Kokoh Kouakou Boniface 
Published: February 2020

As one of the attractive fuels in the direct alcohol fuel cell applications, the ethylene glycol electrooxidation was investigated in alkaline medium on Pd-based bimetallic catalysts (PdM/C, where M = Ni, Ru). These electrode materials were synthesized by polyol method, using ethylene glycol as both solvent and reducing agent. The resulted anode catalysts displayed effectiveness toward the oxidation of ethylene glycol. The latter molecule was also scrutinized as potential fuel which can be converted by cogeneration into energy (5.2 kWh kg-1) and particularly to added value product. Ex situanalytical measurements with liquid chromatography/Mass spectrometry provided evidences on the identification of glycolate as the main reaction product on the PdM/C anode materials (Figure 1).
The identification of some adsorbed intermediates and the final reaction products, was also supported by combining electrochemical (cyclic voltammetry, chronoamperometry) and in situreflectance infrared spectroscopy experiments. The PdNi/C catalyst showed the highest intrinsic catalytic activity for the ethylene glycol oxidation. From FTIR experiments our findings gave evidences that the initial molecule skeleton was conserved and carbon monoxide was observed in a low amount.
Acknowledgements
R. Garcia Da Silva gratefully acknowledges FAPESP (2012/07464-0; 2013/25632-0) and CNPq for his fellowship.
Reference

L.M. da Palma, T.S. Almeida, V.L. Oliveira, G. Tremiliosi-Filho, E.R. Gonzalez, A.R. de Andrade, K. Servat, C. Morais, T.W. Napporn, K.B. Kokoh, RSC Adv., 4, 64476 (2014).

Figure 1. Glycolate1isolated and identified by LC-MS as the main compound issued from the ethylene glycol oxidation at the Pd-M/C (M = Ni and Ru) catalysts in alkaline medium.

Figure 1
Nickel-Rare Earth (RE=Ce,Dy,Sm) Electrodes for H2O2 Reduction in Direct Borohydride Fuel Cells
Authors: Santos Diogo M.F. , Cardoso David , Sljukic Biljana , Sequeira Cesar A.C. , Macciò Daniele , Saccone Adriana 
Published: February 2020

Direct borohydride/peroxide fuel cells (DBPFCs) use sodium borohydride (NaBH4) as an anodic fuel and hydrogen peroxide (H2O2) as the oxidant. DBPFCs show higher theoretical cell voltage and energy density than most low temperature fuel cells. Furthermore, the fact that both fuel and oxidant are liquids at room temperature simplifies their storage, handling, thermal management and internal processing [1]. For these reasons, DBPFCs are promising alternatives as power sources for space, underwater, and specific terrestrial applications where oxygen is not available.
To push forward the DBPFC, it is necessary to develop efficient electrocatalytic materials towards hydrogen peroxide reduction reaction (HPRR), at the lowest possible cost. Nickel (Ni) alloys were found to possess good catalytic activities for HPRR [2]. Recently, it was shown that Ni-rare earth (RE) alloys presented improved catalytic activity for hydrogen evolution reaction, at much lower cost [3]. However, nothing is known about the effects of RE elements on the electrocatalytic behavior of Ni towards the HPRR.
In this study, the HPRR is evaluated in six different Ni-RE intermetallic alloy electrodes, namely nickel-cerium (Ni-Ce), nickel dysprosium (Ni-Dy) and nickel-samarium (Ni-Sm) with 5 and 10 at.% of RE metal. The alloys were prepared by arc melting, starting from the stoichiometric amounts of the two parent metals, and analyzed by XRD and SEM coupled with EDS. The results were directly compared with single Ni electrode in the same experimental conditions.
Electrochemical experiments were performed using a standard three-electrode setup, using each of the Ni-RE alloys as a working electrode. The alloys were tested in 2 M NaOH + 0.05 M H2O2 aqueous electrolytes, at temperatures ranging from 25 to 45 ºC. Cyclic voltammetry (CV), linear scan voltammetry (LSV), chronoamperometry (CA), and chronopotentiometry (CP), were used to investigate the electrodes activity for HPRR reduction in alkaline media. CVs of the alloys presented a well-defined cathodic peak. Plots of peak currents and peak potentials as a function of the potential scan rate allowed calculation of the number of exchanged electrons and of the charge transfer coefficients for the studied temperature range. CA measurements demonstrated good stability of the tested systems.
References
1. D.M.F. Santos, C.A.C. Sequeira, Sodium borohydride as a fuel for the future, Renew. Sustain. Energy Rev. 15 (2011) 3980.
2. A.E. Sanli, A. Aytaç, Electrochemistry of The Nickel Electrode as a Cathode Catalyst In The Media Of Acidic Peroxide For Application of The Peroxide Fuel Cell. ECS Trans. 42 (2012) 3.
3. D.S.P. Cardoso, L. Amaral, D.M.F. Santos, B. Šljukić, C.A.C. Sequeira, D. Macciò, A. Saccone, Int. J. Hydrogen Energy 40 (2015) 4295.
(Invited) Combined Experimental-Numerical Approaches for Transport Characterization in Nano and Micron-Sized Multi-Component and Multi-Functional Materials
Authors: Haussener Sophia 
Published: February 2020

Porous and heterogeneous materials are core components in energy conversion and storage devices such as batteries, fuel cells and electrolyzers, or photoelectrochemical fuel generators. The heterogeneity and structural complexity of these components are a result of three main drivers: i) The multi-functional nature of the applications requiring the presence of various functional materials in close vicinity, ii) nano- and micron-scale structuring of the material required to overcome the bulk material transport limitations, and iii) cheap and simple synthesis methods resulting in stochastic and complex morphologies. Consequently, understanding of the multi-physical transport phenomena and optimization of the component for enhanced performance, requires an accurate modelling and prediction of the transport properties, which heavily rely on the complex nano to micron-scale morphology.
In this presentation, I will show how a previously developed combined experimental-numerical approach1 can be used for the accurate numerical characterization of the heterogeneous components’ transport properties. The methodology consists of (i) the experimental characterization of the material’s exact microstructure via non-intervening, non-destructive imaging techniques, and the subsequent use of this data in (ii) the discrete-scale numerical determination of the medium’s effective transport properties in conjunction with continuum-scale theory. This approach can be extended by using digital image processing on the structure data2,3 to allow for artificial changes in the morphological characteristics – corresponding to real variations in the fabrication process – and subsequent investigation of the changes in the material’s transport properties.
I will show results from the application of the combined experimental-computational methodology to three morphologically complex components at very different length-scales and in three different applications: (i) nano-structured multi-component photoelectrodes for the production of solar fuels, (ii) nano-structured porous electrodes in high-temperature electrolysis, and (iii) porous ceramic receivers for the production of concentrated solar power. The approach allowed to quantify for the first time morphological and transport properties of nano-structured photoelectrodes (example i), to characterize novel transport properties such as permeability for porous electrodes in high-temperature electrolysis (example ii), and to propose pore-scale engineering design guidelines for optimized structures of solar receivers (example iii).
1 J. Petrasch, Ph.D. thesis, ETH Zurich, 2007.
2 S. Haussener, and A. Steinfeld, Materials, 2012, 5, 192–209.
3 S. Suter, A. Steinfeld, and S. Haussener, Int. J. of Heat and Mass Transfer, 2014, 78, 688-698.
4 S. Suter, and S. Haussener, JOM, 2013, 65, 1702-1709.
Development of Ionic Liquid-Tagged Carbohydrate Building Block for Electrochemical Glycosylation
Authors: Nokami Toshiki , Sasaki Norihiko , Isoda Yuta , Itoh Toshiyuki 
Published: February 2020

Recently we have developed an electrochemical method for oligosaccharide synthesis based on the automated electrochemical assembly (AEA) of carbohydrate building blocks. This method enables us to access fully protected oligosaccharides rapidly in a preparative scale; however, the assembly of building blocks is one of the steps of oligosaccharide synthesis. In order to increase efficiency of the entire process, it is important to introduce a strategy which facilitates separation and purification of oligosaccharides thus-obtained.
Separation tags are small molecules which are covalently attached to the substrates to make the separation step easier and faster. There are several tags including a fluorous tag, an ionic liquid tag, and others which have already been introduced into oligosaccharide synthesis. In this study, we introduced an ionic liquid tag to the building block for electrochemical glycosylation, because we presume that an ionic liquid tag works not only as a separation tag but also as an electrolyte and a reservoir of the counter anion for the reactive intermediate of glycosylation. Here we report the development of a novel ionic liquid tag and its application for electrochemical glycosylation.
The developed benzyl ether-type ionic liquid tags were prepared from the corresponding precursors that can be prepared in a single step by the reaction of tertiary amines and introduced to a thioglycoside building block also in a single step with high yields. Electrochemical glycosylation of the thioglycoside equipped with the ionic liquid tag affords the corresponding disaccharides which can be purified easily by washing with water and organic solvent sequentially. In the presence of palladium carbon under the hydrogen gas atmosphere, removal of the tag and benzyl protecting groups of hydroxyl groups can be performed to obtain the fully deprotected disaccharides.