bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication of Faceted Metal Nanocrystal Electrodes By Solid-State Dewetting
Authors: Sharma Rakesh Kumar , Harsha Shreyas , Mul Guido , Altomare Marco 
Published: February 2024

Electrochemical reactions are electrode-structure sensitive and hence microstructural properties of the (electro)-catalysts such as size, shape, exposed facets, and grain boundaries, among others, strongly affect the activity, selectivity, and stability.1, 2 Conventional methods based mainly on wet-chemistry have been widely adopted to synthesize nanocrystal (NC) electrocatalysts, and proved suitable to control their features. However, these methods require several synthesis steps, which increase the production time and complexity, and resulting particles often feature a complex composition (due to impurities such as ligands or templating agents) and suffer from durability issues, due e.g. to particle detachment from the substrates.
We explore solid-state dewetting (SSD) as an alternative way to produce metal nanocrystal electrocatalysts while overcoming various challenges intrinsic of conventional approaches.3, 4 Dewetting is the heat induced agglomeration of thin metal films into particles. Taking Pt as a case study, we have investigated the effect of various SSD parameters such as metal film thickness, substrate crystallographic features, and dewetting conditions (time/temperature/atmosphere) on the physicochemical properties of the resulting dewetted metal NCs. Under optimized conditions, dewetting forms monodispersed faceted Pt nanocrystals of tunable size. Low- or high-index facets can be designed (as shown in the figure below) by tuning the substrate orientation and dewetting conditions (e.g., T, dewetting gas). In general, dewetted Pt NCs show higher (ESCA-normalized) activity towards hydrogen evolution reaction (HER) compared to Pt thin films, and their mass activity is comparable to the state-of-the-art Pt/C. The talk will delve into correlations between microstructure (grain size, shape and facets etc.) and the electrochemical performance of dewetted NCs.
From a general point of view, dewetted NCs show intriguing electrochemical and mechanical properties, and hence dewetting appears to be a promising approach for preparing active and robust nanostructured (electro)-catalysts for various applications. In ongoing work, we investigate dewetting to deposit catalysts on gas diffusion layer (GDL) electrodes and test their performance in PEM lab-scale electrolyzers.

Figure 1
Materials Integration and Catalyst Interfaces in Anion Exchange Membrane, Low Temperature Electrolysis
Authors: Alia Shaun M , Kreider Melissa , Volk Emily K. , Chan Ai-Lin , Clauser Arielle L , Sugar Josh D 
Published: February 2024

As an energy carrier, hydrogen has unique advantages due to its high energy density, ability for long-term storage, and the ability to convert between chemical bonds and electricity. [1] Although hydrogen currently has a small role in energy pathways, low-cost renewable power sources can allow for significant growth. Anion exchange membrane (AEM) electrolyzers leverage several advantages, including a zero-gap approach that typically improves upon the efficiency of traditional alkaline systems. [2] Compared to proton exchange membrane (PEM) electrolyzers, the high pH also allows for platinum group metal-free (PGM-free) catalysts and component coatings (transport layers, separators) that can reduce system cost and improve long-term durability. In recent years, membrane advancements have further enabled higher AEM performance, particularly in supporting electrolytes. [3]
This presentation includes an overview of efforts in AEM electrolysis and focuses on materials choices and their integration. While components are readily available that can achieve high performance, individual properties and their interactions create integration challenges. [4] In catalyst and transport layers, large particle sizes and lower catalyst conductivity coupled with the high distance between transport layer fibers can lead to lower catalyst utilization and high catalyst layer resistances. The ionomer, while critical for ionic transport in water, is primarily needed in supporting electrolytes for structural integrity, and changes to the ionomer content, type, and its distribution throughout the catalyst layer have been explored for its effect on performance and durability. These experiments demonstrate the complications of developing a single set of materials and test protocols for component evaluations.
References
[1] B. Pivovar, N. Rustagi, S. Satyapal, The Electrochemical Society Interface
2018, 27, 47.
[2] S. Alia, D. Ding, A. McDaniel, F.M. Toma, H.N. Dinh, Chalkboard 2-how to make clean hydrogen. The Electrochemical Society Interface
2021,
30 (4), 49.
[3] S. M. Alia, HydroGEN: Low Temperature Electrolysis, https://www.hydrogen.energy.gov/pdfs/review21/p148a_alia_2021_p.pdf 2021.
[4] H. Dinh, HydroGEN Overview: A Consortium on Advanced Water Splitting Materials, https://www.hydrogen.energy.gov/pdfs/review22/p148_dinh_2022_o.pdf 2022.
The Power of Reference Electrodes in AEM Electrolysis
Authors: Guruprasad Naveen , de Groot Thijs Theodorus , van der Schaaf John 
Published: February 2024

The use of reference electrodes is a powerful diagnostic tool to determine the overpotentials associated with oxygen and hydrogen evolution reaction. Yet, the use of reference electrodes in flow cells is still uncommon and provides several challenges especially related to the stability of the potential of the reference electrode. This study investigates the use of a reference electrode in a well-performing iridium-free AEM flow cell with a cell potential of <1.8 V @ 1.5 A cm-2. The reference electrode consists of electrically insulating foil with two platinum wire electrodes on one side as shown in Figure 1(left). A small micro-current is passed through the platinum wires to maintain hydrogen coverage on the reference electrode to establish equilibrium cell potential. The use of the reference electrode shows that the platinum-ruthenium cathode performs particularly well with an overpotential of <0.1 V @ 0.2 A cm-2.
The reference electrode also is useful for the study of cell degradation. One of the major challenges of coupling electrolyzer directly to renewables are reverse currents flowing after shutdown in alkaline and AEM electrolyzers [1]. In this study, polarities were reversed to simulate these reverse currents. This lead to a significant increase in cell potential. It is clearly evident from Figure 1(right) that the cathode overpotentials increased significantly after this reverse current application, thereby indicating that the platinum-ruthenium cathode is vulnerable to reverse currents.
[1]Ashraf Haleem et al, Effects of operation and shutdown parameters and electrode materials on the reverse current phenomenon in alkaline water analyzers, Journal of Power Sources, Volume 535, 2022, 231454, ISSN 0378-7753, https://doi.org/10.1016/j.jpowsour.2022.231454

Figure 1
Iridium Single Atom Catalysts for Oxygen Evolution Reaction in Acidic Medium
Authors: Rouger Jean , Cavaliere Sara , Jaouen Frederic , Jones Deborah J. , Dufour Fabien , Georges Maureen , Thuilliez Julien 
Published: February 2024

In order to reduce CO2 emissions and produce clean hydrogen one solution is to use sustainable energies (wind, solar or hydraulic) coupled with water electrolyser to produce H2 and store it before use it in fuel cell. The electrolyzer based on proton exchange membranes (PEM) is a promising technology because it can reach high current density (2 A.cm-2) [1] and can be easily coupled with intermittent energy sources [2]. However, the acidic conditions and working temperatures (80 °C) require the use of noble metals. On the anode side the oxidative condition prevents the use of carbon supported catalyst and the best catalyst for the oxygen evolution reaction (OER) so far is IrOx.
The use of Ir single atom catalyst (SAC) supported on conducting oxide is a promising way to reduce the quantity of the scarce and expensive noble metal, increasing the electroactive surface and durability. SACs present an excellent dispersion and activity [3] and some conducting oxides are very promising regarding electrical conductivity and stability under oxidative conditions [4]. There are different approaches to prepare Ir SAC (wet impregnation, co-precipitation, photoelectrochemical reduction...) [3], whose success mainly depends on the nature of the Ir precursor, its interaction with the support and the thermal treatment temperature/duration. Some research groups have prepared and characterized Ir SAC on indium-tin oxide [5] but the activity and stability still need to be improved.
The objective of this communication is to present the synthesis and the characterization of IrSAC on different conducting oxide supports. Ir precursor was synthesized and deposed on various supports. The physical characterization entails XRD, TEM, MEB, EDX to assess the morphology and composition of the catalyst. Spectroscopic analysis like XPS and XAS brings information on the chemical environment of Ir sites, while electrochemical measurements give information on the OER activity and stability of the catalyst.

References

[1] C.D. Ferreira da Silva et al., ACS Catal., 2021, 11, 4107-4116
[2] O. Schmidt et al., Int. J. Hydrog. Energy, 2017, 42, 30471-30492
[3] J. Liu, ACS Catal., 2017, 7, 34-59
[4] Moriau et al., ChemCatChem, 2022, 14, e202200586
[5] D. Lebedev et al., ACS Cent. Sci.
2020, 6, 1189-1198
[6] Q. Wang et al., ACS Catal.,
2020
, 142, 7425-7433
Advancing Fundamental Understanding of Electrolyzers for Cost-Effective Green H2 Production
Authors: Dubouis Nicolas 
Published: February 2024

Reaching net-zero by 2050 is critical to limit global warming to below 2°C by 2100. Renewable energy will play a vital role in this transition, and one of the key challenges is to deploy them at a multi-GW scale. TotalEnergies’ Hydrogen R&D department is committed to developing green H2 production and storage technologies to meet this challenge.
In this talk, we will focus on alkaline electrolysis, which has been around for over a century but still presents significant challenges for GW-scale projects. We will discuss how our research can improve the efficiency, durability, and cost-effectiveness of alkaline electrolyzers. For instance, we will demonstrate using a simplified electrolyzer model that a good understanding of the kinetics of ageing phenomena can drastically impact the H2 production cost and the maintenance philosophy of an industrial plant. Based on these observations, we will propose a methodology to refine this understanding, and to better grasp the effect of intermittent operation of the electrolyzer on its ageing. Finally, we will highlight some fundamental findings made by academia that we believe could be good to explore to increase alkaline electrolyzer performance.
In conclusion, there is a need to increase the dialogue between industry and academia to tackle the challenges of green H2 production at the multi-GW scale. By working together, industry and academia can develop more efficient and cost-effective green H2 production technologies, bringing us closer to achieving our ambitious multi-GW scale targets.
FC-Platform Activities and Post Analysis of Durability Tested MEA
Authors: Takeuchi Norimitsu , Shinohara Kazuhiko , Kawase Motoaki , Imai Hideto , Sodeyama Keitaro 
Published: February 2024

FC-Platform, specialized in PEFC's analysis and evaluation, has been launched as a NEDO's funded project. FC-Platform consists of 5 groups of the electrochemical evaluation, simulation, materials analysis, materials informatics and management, involves several institutions. The numbers of various materials research themes have been also running in the NEDO's project. FC-Platform provides better directions of improving for these materials research through analysis and evaluation of their materilas. Moreover, Materials informatics (MI) have been applyed to the development of thier matrials in several themes. Visualizing and predicting phenomena in the PEFCs are essential for realizing high performance and durability at a material level. Therefore, we are focusing on advanced visualization techniques and trans-scale stack modeling development. We also had post analysis and evaluation of the MEAs under long term road-cycle test.
This work was supported by a NEDO FC-Platform project commissioned by th e New Energy and Industrial Technology Development Organization (NEDO).
(Invited) Recovery Of Silver And Silicon From EoL PV Modules
Authors: Chichignoud Guy , Parsa Yohan , Iwaszko Victorien , Luo Yun 
Published: February 2024

Photovoltaic modules global expansion has been dynamic over the last 20 years and is on the verge of becoming massive with the necessary ongoing energy transition. This development raises legitimate concerns of i) raw materials availability and ii) handling of modules as a waste after their decommissioning. End of Life (EoL) modules are indeed a powerful source of critical raw materials that worth being fully exploited and optimized to reduce the demand on natural resources and energy (>50MWh/t of PC-Si) to produce fresh modules whilst addressing the matter of wastes. We shall know that 6 tons of natural resources are needed to produce one ton of PV-grade Si, and the share of critical material Ag for PV production accounts already for more than 13% of global consumption. However, EoL module recycling has been poorly developed so far, mostly because of the difficult delamination stage necessary to release precious metals and Silicon. Different approaches, involving shredding, machining, solvents, flashing light have been investigated by different institutes or companies to delaminate the module structure and recycle metals, but none of them successfully demonstrated the recovery at large scale, suffering from a lack of purity, efficiency or scalability. In this context, ROSI developed an innovative route coupling different key steps to produce Silver and Silicon at industrial scale by recycling EoL modules. In order to address the varsity of polymer structures in PV panels, a thermal process based on pyrolysis ensures a generic approach of delamination to convert 100% of polymers into gas, thus releasing cell fragments. A mild chemical etching step then achieves the full separation of Silver fingers from the surface of Silicon, avoiding the use of harsh chemicals generally used in the recovery of metals from electronic wastes. A dedicated sortation process finally allows to recover high purity glass, copper, Silicon and Silver as depicted in Figure 1.
Based on the thermal behaviour of different mixes of polymers, pyrolysis process has been optimized to ensure the full conversion of polymers in gas whilst limiting thermal budget regardless of the initial composition of the PV module. This optimization phase will be presented and coupled with the mild wet etching technology developed to obtain silver fingers. Characterizations of recoveredmaterials will be presented, together with their high value applications.

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Challenges of Scaling-up the Wet-Chemical Synthesis of β-Li3PS4
Authors: Gries Aurelia , Langer Frederieke , Schwenzel Julian 
Published: February 2024

All-solid-state batteries are considered the next generation in battery technology due to increased energy and power density as well as freedom of design, e.g. by constructing batteries in bipolar stacks. Solid-state electrolytes offer advantages over conventional liquid electrolytes, such as greater thermal safety, because of high melting points, and higher mechanical strength. This is believed to suppress growth of lithium dendrites and, therefore, opens up the possibility of using a lithium metal anode. One promising material group is sulfides, because they are ductile and have a good intrinsic ionic conductivity. Some sulfide solid electrolytes can be synthesized wet-chemically. This offers advantages like tailoring the particle size, working at ambient temperatures, short synthesis durations, stabilizing meta-stable phases by using new synthesis routes and the possibility of transferring the routine to a continuous process. The particle size and morphology are important factors regarding the suitability to produce all-solid-state batteries wherefore small (< 10 µm) and homogeneous particles are preferred. The present research mainly focusses on finding and improving new materials and their usage in battery production, but there is little progress on mass-production of sulfide solid electrolytes. To scale-up a synthesis, multiple aspects have to be considered since they often influence both product and process. Therefore, an analysis and optimization of the synthesis process is necessary to support the development and to increase the economic attractiveness of new materials.
In this presentation, the reaction enthalpy and the influences of concentration and solvent variation of synthesizing the sulfide solid electrolyte β-Li3PS4 are examined and discussed. β-Li3PS4 is synthesized by mixing lithium sulfide and phosphorus pentasulfide in a solvent, e.g. THF, at ambient conditions. After removing the solvent, heat treatment is used to obtain the crystalline product. We found that the mixing step contains a highly exothermic reaction and determined the reaction enthalpies using a reaction calorimeter. To handle the heat development, two options were investigated: First, the solvent amount was increased and second, the synthesis was performed using alternative solvents with different thermal properties. The examined solvents are THF, ethyl acetate and ethyl propionate. The reaction enthalpies of the synthesis in different solvents are compared. A strong influence on the particle size and morphology caused by the amount and choice of solvent could be detected by SEM. While the particle size increases with increasing amount of solvent, the shape of the particles alters under solvent variation. With low solvent amount the smallest particle sizes (< 10 µm) are synthesized. Finally, suggestions regarding the scale-up will be given based on the findings of these examinations.
(Invited) Chemical and Microstructural Reaction Paths in High-Temperature Alloys in Contact to Molten Salts
Authors: Geers Christine 
Published: February 2024

Molten salts for thermal energy storage applications have gained attention in recent years. Simultaneously, demands on salt melts are also getting higher: higher thermal stability, availability, and economic feasibility.
Maybe the most crucial factor, however, is the possibility to match a suitable containment material for salt melts. By increasing operation temperature, material degradation processes commonly accelerate beyond tolerable thresholds. These thresholds are referring to material integrity, strength, and local attack.
It turns out that every salt melt hereby reacts along characteristic pathways influencing alloys’ surface chemistry and underlying microstructures to very deep levels.
High-temperature alloys depend on their carefully balanced elemental compositions. During this presentation, we will explore how subtle salt-induced compositional shifts have a large and rapid influence on microstructural properties in alloys and thereby on their performance assessment.
(Invited) The Internal Oxidation Mechanism of Ti60 Alloy in NaCl-coated Environment at 600o C
Authors: Chen Wenzheng , Li Rui , Liu Li , Wang Fuhui 
Published: February 2024

When serving in the marine environment, the blades of aircraft engines will suffer serious high-temperature corrosion and their service life will be shortened. This is because the water vapour and salt particles (mainly NaCl) in the marine atmosphere will inevitably be involved in the engine, resulting in severe corrosion of materials. Previous studies on the degradation of titanium alloy under NaCl mainly focused on the active oxidation mechanism, while the mechanism of internal oxidation, which can significantly damage the mechanical properties of the titanium, is not clear. In addition, internal oxidation appears microstructure sensitivity, indicating that microstructure design may be an important way to improve high-temperature corrosion resistance in the marine environment.
Consequently, for further understanding the internal oxidation mechanism and the influence of microstructure on corrosion, the composition and morphology of the internal oxidized layer of the Ti60 samples, which corroded with NaCl precoated at 600 oC in moist O2 flow for 100 h, have been studied.
According to the results, Ti2O formed within the internal oxidized layer. With the thermodynamic calculation results, this observation proves that internal oxides do not result from the oxidation of metal chlorides. As it is known that titanium has a high affinity to oxygen, the internal matrix turns into titanium oxides with different valence states directly, while TiCl4(g) formed from active oxidation further transports outward and is oxidized at the position with high P(O2).
The α secondary phase, located inside the β phase, is more sensitive to NaCl-induced corrosion than the α lamellar outside the β phase. This is because β phase and phase boundaries provide more high-energy channels for corrosive media transport to the α secondary phase, which results in severe loss of metallic elements and oxidation. The design of the α secondary phase may be one essential point for developing titanium alloys with a good combination of mechanical properties and corrosion resistance in marine environments.

Figure 1
(Invited) Design of Lithium Battery Electrolytes Based on Electrode Potentials
Authors: Yamada Yuki 
Published: February 2024

Lithium (Li) metal is an ideal battery anode with low electrode potential (-3.045 V vs. SHE) and high theoretical capacity (3860 mAh g-1, 2060 mAh cm-3). However, its critical problem is a low Coulombic efficiency (CE), which is caused the thermodynamic instability of a Li/electrolyte interface because of the strong reducing ability of Li metal. Since Li electrode potential (E
Li) is located far below the cathodic limit of the electrolyte's potential window, the electrolyte components are inevitably reduced and decomposed on the Li metal anode (Fig. 1). Some of the decomposition products function as solid electrolyte interphase (SEI) to suppress further electrolyte decomposition. Various electrolytes and additives have been proposed to form a stable SEI on Li metal, which leads to higher CEs. However, the correlation between CE and SEI is still unclear.
Here we report E
Li as a quantitative and thermodynamic descriptor of the CEs of Li metal anodes.1 We measured E
Li in various electrolytes with reference to 1 mM ferrocene as an internal standard. The obtained E
Li varied significantly (up to 0.6 V) depending on electrolyte formulations. We also evaluated the CEs of Li plating/stripping in various electrolytes without ferrocene. Based on these results, we found that the CEs are correlated with E
Li (Fig. 2). The CE increased with increasing E
Li, suggesting that the reductive decomposition of electrolytes was suppressed at high E
Li (lower reducing ability of Li).
Theoretically, E
Li is directly determined by the chemical potential of Li+ (μ
Li+) in the electrolyte. Hence, E
Li, that is the reducing ability of Li, can be controlled by designing an electrolyte focusing on μ
Li+. Raman Spectroscopy revealed that the formation of ion pairs is essential for increasing the μ
Li+ and upshifting the E
Li. This finding provides fundamental science that can tune the μ
Li+ and E
Li to increase the CE of Li metal anodes.
1. Seongjae Ko, Tomohiro Obukata, Tatau Shimada, Norio Takenaka, Masanobu Nakayama, Atsuo Yamada, Yuki Yamada, Nat. Energy, 7, 1217-1224 (2022).

Figure 1