bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eco-Friendly All Water-Based Solution Process for Robust Ag Nano-Mesh Transparent Electrodes
Authors: sung Min Lee , In Hyeok Oh , hong Sik Eom , In Hyeok Oh 
Published: December 2020

Transparent conducting electrodes have attracted substantial attentions as an essential component of various optoelectronic devices. Recently, the grid-structured metal mesh electrodes are considered as highly efficient transparent electrodes that possess high optical transmittance while maintaining sufficient electrical conductivity and are suitable for flexible conductors with isotropic electrical conductivity. Here, we report a simple and effective approach for the fabrication of highly transparent Ag nano-mesh prepared by all water-based solution process. The Ag mesh electrodes were formed by combination of colloidal gold nanoparticles deposition and silver enhancement. The optical and electrical properties of the Ag mesh can be finely tuned by varying condition of gold nanoparticle deposition and silver enhancement. The smallest feature size of the obtained metal mesh patterns is about 700 nm with a thickness of 30-60 nm. The transparent electrodes with the Ag nano-mesh structure exhibit not only excellent electrical conductivity with a sheet resistance of 70 Ω/sq at a transmittance of 96.2% but also strong adhesion strength to substrate which is confirmed by peeling off test. Our all water-based solution processed metal mesh electrodes is applied to transparent heater which is able to heat up to 250 °C at 7 V. Through this study, Not only fabrication of high performance metal mesh but also low cost fabrication without any hazardous wastes is succeeded.
This research was funded and conducted under [the Competency Development Program for Industry Specialists] of the Korean Ministry of Trade, Industry and Energy(MOTIE), operated by korea Insstitute for Advancement of Technology (KIAT). (No. P0012453, Next-generation Display Expert Training project for Innovation Process and Equipment, Materials Engineers)
Empirical Mode Decomposition Applied to Proton Exchange Membrane Electrolyzer for Non-Intrusive Diagnosis
Authors: Aubras Farid , Damour Cedric , Benne Michel , Bessafi Miloud , Lin-Kwong-Chon Christophe , Grondin-Perez Brigitte , Deseure Jonathan , Kadjo Jean Jacques Amangoua 
Published: December 2020

The water electrolysis based on Polymeric Electrolyte Membrane technology (E-PEM) is an interesting solution for efficient carbon-free hydrogen production. By the end of the 21st century, the contribution of hydrogen will continue to achieve significant rate in the energy mix. As there have been advances of efficient end-use technologies, hydrogen could even become the main energy carrier [1]. Regarding diagnosis purposes, Empirical Model Decomposition (EMD) method has proven to be a versatile and efficient tool to analyze non-stationary signals and extract features from them [2].
As a starting point of its decomposition, oscillations are considered, at a local level, as the sum of a specified number of high and low frequency contributions called Intrinsic Mode Functions (IMFs). IMFs represent the natural oscillatory mode embedded in the signal and work as the basis functions, which makes EMD a self-adaptive method. fig.1 shows the decomposition of the E-PEM current into a finite set of intrinsic mode functions.
This study presents a non-intrusive tool designed to fulfill on-line diagnosis requirements. Indeed, the proposed method does not require any excitation signal or stabilization period as Electrochemical Impedance Spectroscopy-based approaches [3]. Therefore, the electrolyzer remains continuously available, even while the diagnosis is being performed. Besides, it only requires measurement of current and has a low computational costs, which are significant economic and technical advantages. Here, EMD has been used to study the anode flow rate dynamics. Several experiments have been conducted and experimental results have demonstrated the effectiveness of the proposed diagnosis tool and its advantages compared to other methods.

Acknowledgements

This project has received funding from the Reunion Island Region and the European Commission – ERDF

References

Barbir, “PEM electrolysis for production of hydrogen from renewable energy sources,” Solar Energy, vol. 78, no. 5, pp. 661–669, May 2005, doi: 10.1016/j.solener.2004.09.003.

Damour, M. Benne, B. Grondin-Perez, M. Bessafi, D. Hissel, and J.-P. Chabriat, “Polymer electrolyte membrane fuel cell fault diagnosis based on empirical mode decomposition,” Journal of Power Sources, vol. 299, pp. 596–603, Dec. 2015, doi: 10.1016/j.jpowsour.2015.09.041.

C. Garcia-Navarro, M. Schulze, and K. A. Friedrich, “Measuring and modeling mass transport losses in proton exchange membrane water electrolyzers using electrochemical impedance spectroscopy,” Journal of Power Sources, vol. 431, pp. 189–204, Aug. 2019, doi: 10.1016/j.jpowsour.2019.05.027.

Figure 1: Intrinsic mode functions decomposition for operating conditions of 1.6 V and 0.5 ml.min-1

Figure 1
Thermal History Induced Surface Restructuring of La0.6Sr0.4CoO3-δ thin-Film Solid Oxide Electrodes and Its Significance for the Catalytic Activity and Stability
Authors: Celikbilek Ozden , Cavallaro Andrea , Kerherve Gwilherm , Fearn Sarah , Chaix-Pluchery Odette , Aguadero Ainara , Kilner John , Skinner Stephen 
Published: December 2020

Thin-films deposited by Pulsed Laser Deposition (PLD) have enabled the fabrication of cathodes for solid oxide cells (SOC) to possess various microstructures, crystalline states and surface chemistry. These films are often subjected to various processing and thermal treatments which influence the chemical activity and stability of the films. Here, we investigate how the catalytic activity and stability is affected by the thermally induced surface restructuring in complex transition metal oxides, in particular, La0.6Sr0.4CoO3-δ (LSC) thin films grown by PLD.(1) To this end, the influence of substrate temperature during PLD as well as post-annealing treatments on the film microstructure and surface chemistry were studied. In comparison to high-temperature grown films, the post-annealed low-temperature grown films showed 2-fold lower degradation rate in the long-term electrochemical tests at 500 °C. The differences in the electrochemical stability were found to be related to the initial microstructure and morphology of the films (Fig 1). The post-annealed low-temperature grown film showed localised Sr-segregation into protruding particles, leaving the remaining surface with catalytically active stoichiometry. On the other hand, the high-temperature grown films showed a fully covered surface with Sr-rich particles, which continued to thicken with time. Here we emphasise the importance of processing and thermal history in the elemental surface distribution, especially for the stability of LSC64 electrodes and propose that it should be considered as among the main pillars in the design of the active surface.
Fig. 1 Top-view (a,d,g) and cross-section view (b,e,h) SEM micrographs and corresponding AFM images (c,f,i) showing the topography of LSC64 films deposited by the PLD: (a−c) LT-grown film, (d−f) postannealed LT-grown film, and (g−i) HT-grown film. (https://pubs.acs.org/doi/10.1021/acsami.0c08308) Reprinted with the permission of the American Chemical Society. Further permissions related to the material excerpted should be directed to the ACS.
(1) Celikbilek, O.; Cavallaro, A.; Kerherve, G.; Fearn, S.; Chaix-Pluchery, O.; Aguadero, A.; Kilner, J. A.; Skinner, S. J.. ACS Appl. Mater. Interfaces 2020, 12, 34388−34401.

Figure 1
Modeling Single and Two-Phase Transport in Thin Porous Layers Using a Composite Continuum-Pore Network Formulation
Authors: Garcia-Salaberri Pablo , Zenyuk Iryna V. , Gostick Jeff T. , Weber Adam Z. 
Published: December 2020

In this work, a composite continuum-pore network formulation is presented to model single and two-phase transport thin porous layers, such as gas diffusion layers in polymer electrolyte fuel cells (PEFCs) and active electrodes in redox flow batteries (RFBs). The formulation can be integrated into CFD codes, thus combining the ease of implementation of continuum-based modeling and the computational power of pore-network modeling. The composite model includes a control volume (CV) mesh at the layer scale, which embeds a cubic pore network [1,2]. The pore-network model is used to determine analytically local anisotropic effective transport properties (local effective diffusivity and permeability), which are mapped onto the CV mesh to simulate transport in the porous transport layer [3,4]. Good agreement is found between the predicted global effective transport properties (global effective diffusivity and permeability) under dry and wet conditions and previous experimental data reported in the literature for Toray TGP-H series carbon paper. Water saturation distributions are also compared with results obtained using X-ray computed tomography [4].
[1] P.A. García-Salaberri, I.V. Zenyuk, J.T. Gostick, A.Z. Weber, Modeling Gas Diffusion Layer in Polymer Electrolyte Fuel Cells Using a Continuum-Based Pore-Network Formulation, ECS Trans. 97 (2020) 615.
[2] P.A. García-Salaberri, Modeling diffusion and convection in thin porous transport layers using a composite continuum-network model: Application to gas diffusion layers in polymer electrolyte fuel cells, Int J. Heat Mass Transf. (2020), submitted.
[3] P.A. García-Salaberri, J.T. Gostick, G. Hwang, A.Z. Weber, M. Vera, Effective diffusivity in partially-saturated carbon-fiber gas diffusion layers: Effect of local saturation and application to macroscopic continuum models, J. Power Sources 296 (2015) 440–453.
[4] P.A. García-Salaberri, G. Hwang, M. Vera, A.Z. Weber, J.T. Gostick, Effective diffusivity in partially-saturated carbon-fiber gas diffusion layers: Effect of through-plane saturation distribution, Int. J. Heat Mass Transf. 86 (2015) 319–333.
Modeling of High-Temperature Multiphase Solid/Molten Carbonate Membranes for CO2 Capture
Authors: Jin Xinfang , Li Xin , Huang Kevin 
Published: December 2020

High-temperature solid/molten-carbonate composite represent an emerging class of CO2 transport membranes to capture CO2 from flue gas with advantages in flux density and selectivity over conventional solvent/sorbent- and polymer-based counterparts. While significant technical progress in these membranes has been made in the past years, a deeper fundamental understanding of CO2 transport mechanisms is still limited. Aimed to bridge this gap, we here report a theoretical study on flux performances of four types of solid/molten-carbonate CO2 transport membranes by analytical and numerical modeling. We first demonstrate the general analytical solutions for CO2 flux of dual-phase solid/MC membranes by solving the partial differential equations (PDEs) along with the boundary conditions. These analytical solutions are then compared with those derived directly from Wagner theory. We also develop numerical CO2 flux solutions and compare them with the existing or our derived analytical solutions to point out the issues with using analytical methods to solve CO2 flux in complex multiphase systems. Finally, we apply our numerical models to simulate CO2 flux in more complex multiphase solid/MC membranes.
From the results, we found that analytical and numerical results are virtually identical for solids with single charge carrier. However, for mixed conducting solids, numerical method is preferred since analytical method cannot solve the nonlinear local concentrations of charge carriers. Application of numerical method to a new three-phase membrane containing a mixed conducting solid, a pure electron conducting solid and molten-carbonate reveals a 75% increase in CO2 flux compared to the two-phase (mixed conducting solid and molten-carbonate) counterpart. The models presented here are expected to provide better fundamental insights and guidance for designing next-generation high-performance CO2 transport membranes.

Figure 1
Development and Engineering of Nanostructured Ternary Catalyst for PEM Fuel Cells: The Role of Electrode Composition in Oxygen Reduction Kinetics
Authors: Sahin Nihat , Akaydin Beril , Ozenler Sibel , Kadirgan Figen 
Published: December 2020

Low-temperature proton exchange membrane fuel cells (PEMFCs), offering significantly higher efficiency compared to conventional heat engines play a crucial role in responding to the growing energy demand, especially for transportation applications. The fundamental understanding of bulk electrocatalysis both in acidic and alkaline media at nanostructured electrodes that possess compositional and structural heterogeneity has a profound effect on electrode kinetics and reaction mechanisms. Because the electrocatalytic activity depends mainly upon the nanoscale size, composition as well as surface properties of the prepared catalyst, development and engineering of advanced electrocatalysts is needed for giving a lead towards unprecedented improvements in electrode performance so in fuel cell systems1. It has hypothesized2 and reported3 that alloying Pt with different metal components (herein Sn and Ni) brings about modifying the electrotonic states such as the d-band centers as well as geometric factors, which has attracted a great deal of attention in electrocatalysis. Moreover, the superior catalytic synergy of nanostructured binary4 and ternary5 electrocatalysts towards oxygen reduction activity was previously reported. To this end, highly active, robust and low-cost carbon-supported ternary nanoparticles (Pt2Sn1Ni1/C) were synthesized using a modified microwave-assisted polyol method6 in diethylene glycol (DEG) without additional protective agents. The morphostructural properties of the catalyst were determined via various advanced-characterization techniques. Cyclic voltammetry (CV) and rotating (ring) disk electrode (RRDE) measurements reveal that the alloying of Pt with Sn-Ni significantly boosts the catalytic activity towards oxygen reduction reaction (ORR) in O2-saturated 0.1M HClO4 electrolyte. The kinetic parameters were assessed through Koutecky-Levich approach. The influence of the alloying structure on the kinetic parameters such as exchange current density, limiting current density, Tafel slopes, reaction rate, and the number of exchanged electrons is extensively discussed.
References:

M. Shao, Q. Chang, J. P. Dodelet, R. Chenitz, Chem. Rev., (2016), 116, 3594.

J. K. Norskov, J. Rossmeisl, A. Logadottir, L. Lindqvist, J.R. Kitchin, T. Bligaard, H. Jonsson, J. Phys. Chem. B, (2004), 108, 17886.

T. Toda, H. Igarashi, H. Uchida, M. Watanabe, J. Electrochem. Soc., (1999), 146, (10), 3750.

C. C. Bakir, N. Sahin, R. Polat, Z. Dursun, Journal of Electroanalytical Chemistry, (2011), 662, 275.

S. Beyhan, N. E. Sahin, S. Pronier, J. M. Leger, F. Kadirgan, Electrochimica Acta, (2015), 151, 565.

N. Sahin, T. Napporn, L. Dubau, F. Kadirgan, J. M. Leger, K. B. Kokoh, Applied Catal. B: Environ., (2017), 203, 72.
Solid Polymer Electrolytes in Lithium Batteries: Challenges and Opportunities for High Specific Energy
Authors: Stolz Lukas , Homann Gerrit , Winter Martin , Kasnatscheew Johannes 
Published: December 2020

Besides enhanced safety aspects, solid polymer electrolytes (SPEs) offer the opportunity to increase the specific energy of secondary batteries by enabling lithium metal as negative electrode in all-solid-state lithium batteries (ASSLB). Therefore, the SPE needs to provide sufficient mechanical strength to prevent short circuits caused by lithium dendrite penetration especially favoured at high current densities.[1] In order to obtain the maximum specific energy of ASSLBs, lithium metal negative electrodes are combined with high voltage positive electrodes, e.g. LiNi0.6Mn0.2Co0.2O2 (NMC622).[2]
In the frame of this work, a novel SPE is applied to NMC622 based ASSLB cells and studied regarding energy limits on battery cell and pack level. In a first step, the active mass loading is systematically increased revealing the specific energy limit on battery cell level. Additionally, the chosen system is applied to a bipolar (serial) stacking aiming towards further energy improvements on battery pack level.[3] In sum, this work reveals remaining challenges but still points towards opportunities enabling the aimed energy increase of ASSLBs.
[1] G. Homann, L. Stolz, J. Nair, I. C. Laskovic, M. Winter and J. Kasnatscheew, Sci Rep, 10, 4390 (2020).
[2] J. Kasnatscheew, M. Evertz, R. Kloepsch, B. Streipert, R. Wagner, I. Cekic Laskovic and M. Winter, Energy Technology, 5, 1670-1679 (2017).
[3] G. Homann, P. Meister, L. Stolz, J. P. Brinkmann, J. Kulisch, T. Adermann, M. Winter and J. Kasnatscheew, ACS Appl. Energy Mater., 3, 4, 3162–3168 (2020).

Figure 1
Methods of Redox Control and Measurement in Molten NaCl-CaCl2-UCl3
Authors: Newton Matthew Laughlin , Hamilton David Ethan , Simpson Michael Forrest 
Published: December 2020

The U.S. Department of Energy is currently supporting the design and planned construction of the Versatile Test Reactor (VTR) capable of performing experiments in a fast neutron field. This will allow for study of the effect of fast neutron irradiation on nuclear fuels, materials, and functional components. The molten salt irradiation experiment will utilize the VTR to study the chemical changes and speciation in molten chloride and/or fluoride salts.
In preparation for future experiments involving irradiation of candidate molten salt fuels, the redox potential measurement and control methods in molten NaCl-CaCl2-UCl3 at 500oC were studied. The goal was to identify a metal/metal chloride redox buffer that can be used to control the redox potential, thereby helping to mitigate the corrosion risks posed by irradiation of the uranium salt fuel. An ideal candidate would both adequately reduce the redox potential and possess a low neutron interaction cross section.
The first metal/metal chloride redox buffer investigated was Zr/ZrCl4. ZrCl4 has a standard state reduction potential of -2.02 V vs. Cl-/Cl2 at 500° C. The standard state reduction potentials for UCl3 and CrCl2 are -2.41 and -1.55 V, respectively. Zr metal should, thus, oxidize to ZrCl4 and control the redox potential at a level that simultaneously prevents Cr corrosion while leaving UCl3 unreduced from the salt.
In order to test Zr metal for redox control, a 6.2-mm diameter Zr rod (99%) was submerged in molten NaCl-CaCl2-UCl3 salt at 600°C. The open circuit potential (OCP) of the salt was measured at a tungsten working electrode vs a Ag/AgCl reference electrode encased in a mullite tube. NiCl2 was added to the salt to simulate the effect of fission on redox potential. After submerging the Zr rod, the measured open circuit potential between the W WE and the RE dropped by -0.63 V over a period of 100 minutes.
There is concern as to whether the rate of reaction of insoluble Zr metal with the salt can keep up with the rate of potential change due to the irradiation of the salt. Other redox buffer candidates being considered include uranium, calcium, and sodium. The latter two choices are attractive because of their predicted solubility in the molten salt, supporting homogenous redox control reactions. The problem with the latter three choices is that amounts contacted with the salt will need to be precisely controlled to avoid reduction of UCl3. OCP measurements will also be reported for molten NaCl-CaCl2-UCl3 using U, Na, and Ca as the redox buffer. Conclusions will be drawn regarding the most effective metal to use in the future VTR experiments in order to control the redox potential of the irradiated salt.
Selective Permeation of Neodymium Through an Alloy Diaphragm in Molten Chloride Systems
Authors: Oishi Tetsuo , Yaguchi Miki , Katasho Yumi , Nohira Toshiyuki 
Published: December 2020

The authors have been investigating a new RE (RE=Dy and Nd) recycling process from Nd-Fe-B permanent magnets, which is characterized by the use of RE-IG (IG=Fe, Ni, Co) alloy diaphragms for separation of REs in molten salts (Fig. 1) [1, 2]. In this process, the RE-IG alloy diaphragm performs as a bipolar electrode and RE ions permeate via three steps: (1) reduction of RE ions to form alloy on the anolyte side of the diaphragm, (2) diffusion of RE atoms in the diaphragm, and (3) oxidation of RE atoms to dissolve into the catholyte as RE ions on the other side of the diaphragm. Because the reaction and diffusion rates depend on the kinds of RE elements and the electrolytic conditions, selective permeation of Dy and/or Nd is possible under an appropriate condition. Using this selective permeation phenomenon through the alloy diaphragms, Dy and Nd can be separately recovered from Nd-Fe-B permanent magnets only by molten salt electrolysis, as shown in Fig. 1.
Recently, the authors reported selective Dy permeation through a RE-Ni alloy diaphragm in molten LiCl-KCl eutectic melts containing NdCl3 and DyCl3 at 450 ℃ [3]. Whereas, in the present study, selective permeation of Nd was examined using a similar experimental setup at the different electrolytic conditions. The obtained molar ratio of permeated Nd/Dy was around 6. Interestingly, EDX analysis revealed that the molar ratio of Nd/Dy in the alloy diaphragm was less than 0.05, which was two orders of magnitude lower than that of the permeated amount. These results suggested that the diffusion rate of Nd atoms in the alloy diaphragm was extremely high compared to that of Dy.

Acknowledgement
This work was partly supported by the New Energy and Industrial Technology Development Organization (NEDO) of Japan.
Reference
[1] T. Oishi, H. Konishi, T. Nohira, M. Tanaka and T Usui, Kagaku Kogaku Ronbunshu, 36, 299–303 (2010).
[2] T. Oishi, Molten Salts (Yoyuen Oyobi Koon Kagaku), 63, 78–83 (2020).
[3] T. Oishi, M. Yaguchi, Y. Katasho and T. Nohira, Rare metal technology 2020, 151–156 (2020).

Figure 1