bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancing Durability of Polymer Electrolyte Membrane Water Electrolyzer through Incorporation of Gas Recombination Catalyst in Membrane
Authors: Li Kui , Khedekar Kaustubh , Wilson Mahlon , Spendelow Jacob S. , Komini Babu Siddharth 
Published: February 2024

Hydrogen will become a critical component of the future energy landscape driven primarily by the growing use of renewable energy sources. Polymer electrolyte membrane water electrolyzer (PEMWE) is a superior technology to facilitate hydrogen production from renewable electricity. However, durability remains a significant challenge for the widespread commercialization of electrolyzers.1 Cross-over of H2 from cathode to anode could lead to explosive mixtures in the anode causing safety concerns during operation. Hydrogen crossover also impacts the durability of the anode catalyst.2 Hydrogen permeation from the cathode to the anode through the membrane reduces the anodic Ir catalyst to a low valence state leading to increased dissolution of the Ir catalyst at a high cell voltage. Utilizing thin membranes (~50µm) can improve the electrolyzer system’s efficiency but also increase the hydrogen permeation, particularly at high pressures.
In this study, we present a methodology to incorporate platinum as a gas recombination catalyst (GRC) layer into commercial membranes, significantly reducing hydrogen permeation rates and mitigating anode catalyst degradation. Membranes with GRC can mitigate the degradation of PEMWE, leading to more efficient and durable PEM electrolysis systems for hydrogen production. The methodology developed enables higher control of the GRC layer properties (Pt particle size and location in the membrane). Ex-situ measurement of hydrogen permeation, shown in Figure 1, indicates a significant reduction in the permeation rate for GRC incorporated NR 212. This study presents a systematic electrochemical evaluation of anode degradation in PEMWE with and without GRC in the membrane using accelerated stress tests. The durability of the GRC during long-term operation is also presented.

Acknowledgment

This research is supported by the U.S. Department of Energy (DOE) Hydrogen and Fuel Cell Technologies Office through the Hydrogen from Next-generation Electrolyzers of Water (H2NEW) consortium.

References

1. Tomic, A. Z., Pivac, I., Barbir, F., Journal of Power Sources (2023) 557

2. Rheinlander, P. J., and Durst, J., Journal of the Electrochemical Society (2021) 168 (2)

Figure 1
Manufacturable Microporous Layers on Sintered Titanium for PEM Electrolysis Applications
Authors: Hill Alex , Goliber Daniel , Gosselin Sean , Tsaknopoulos Derek , Kar Piyush , Papandrew Alexander B 
Published: February 2024

Renewed interest in green hydrogen has prompted a re-examination of the components of proton-exchange membrane water electrolyzers to improve stack durability and lower net hydrogen cost. A key component identified as a driver of cell performance and durability is the anode porous transport layer (PTL). The PTL dictates electrical resistance between anode and flow field, manages two-phase flow at the anode interface, and sinks heat from the electrolysis reaction.
Efforts to optimize the PTL have typically focused on limiting titanium passivation and optimizing delivery of water and discharge of oxygen at the anode. However, recent work has shown another important effect related to the contact area of the PTL with the anode catalyst layer. Multiple investigators have shown that highly flat and smooth PTLs enhance cell durability, particularly in the case of low anode catalyst loadings (< 0.5 mgIr/cm2). In those studies1–5, commercial PTLs were modified to obtain more uniform surfaces. In some cases this is effected by attachment of finely structured microporous layers (MPLs) that improve catalyst utilization and eliminate localized heating.
An integrated manufacturing approach is required to enable commercial adoption of advanced PTLs featuring microporous layers. In this contribution, we investigate multiple routes and materials systems for obtaining manufacturable MPLs. We assess the relative merits of each method with respect to feasibility and resultant component characteristics, and validate ex situ characterization with single-cell electrolyzer durability testing using catalyst-coated membranes with low Ir loadings.

References

(1) Lettenmeier, P.; Kolb, S.; Sata, N.; Fallisch, A.; Zielke, L.; Thiele, S.; Gago, A. S.; Friedrich, K. A. C Energy Environ. Sci.
2017, 10 (12), 2521–2533. https://doi.org/10.1039/C7EE01240C.
(2) Kang, Z.; Yang, G.; Mo, J.; Yu, S.; Cullen, D. A.; Retterer, S. T.; Toops, T. J.; Brady, M. P.; Bender, G.; Pivovar, B. S.; Green, J. B.; Zhang, F.-Y. Int. J. Hydrog. Energy
2018, 43 (31), 14618–14628. https://doi.org/10.1016/j.ijhydene.2018.05.139.
(3) Lee, J. K.; Lee, C.; Fahy, K. F.; Kim, P. J.; LaManna, J. M.; Baltic, E.; Jacobson, D. L.; Hussey, D. S.; Stiber, S.; Gago, A. S.; Friedrich, K. A.; Bazylak, Energy Convers. Manag.
2020, 226, 113545. https://doi.org/10.1016/j.enconman.2020.113545.
(4) Schuler, T.; Ciccone, J. M.; Krentscher, B.; Marone, F.; Peter, C.; Schmidt, T. J.; Büchi, F. N. Adv. Energy Mater.
2020, 10 (2), 1903216. https://doi.org/10.1002/aenm.201903216.
(5) Lee, J. K.; Schuler, T.; Bender, G.; Sabharwal, M.; Peng, X.; Weber, A. Z.; Danilovic, N. Appl. Energy
2023, 336, 120853. https://doi.org/10.1016/j.apenergy.2023.120853.

Figure 1
Present and Future Perspectives on Fuel Cell Membrane Chemical Stability
Authors: Yandrasits Michael 
Published: February 2024

Durability is key to the value proposition of proton exchange membrane (PEM) fuel cells for transportation applications. Ultimately, fuel cell vehicles need to match the lifetimes of diesel powered trucks, and last longer than lithium batteries, for widespread adoption[1]. The burden of reaching these aggressive targets falls on all components of the system, stack, and membrane electrode assembly. Of these, membrane durability remains an important area of research, in particular the chemical stability of the ionomer. The recognition of the ‘simple unzipping’ of the perfluorosulfonic acid (PFSA) backbone by hydroxyl radicals (HO·)[2],[3] and the subsequent introduction of cerium radical scavengers[4],[5] mark significant advancements in fuel cell lifetimes. Yet, even with this technology, it is unclear if this class of membranes can meet the 25,000+ hours required for heavy duty applications without additional improvements. Furthermore, recent proposals to restrict usage of fluorochemicals in many applications[6] presents a risk to the rapidly growing PEM fuel cell and water electrolysis markets. This talk will outline recent work that looks beyond simple peroxide degradation of PFSA ionomers and highlight the role of other reaction mechanisms suspected in accelerated fuel cell durability testing. Analysis of effluent water for ionomer fragments during these tests provides a greater understanding of the degradation mechanisms and suggests additional pathways beyond back-bone unzipping. Not only are these fragments useful in inferring reaction mechanisms, but there is also evidence they adsorb to the platinum surface, ultimately adding to performance decay. In other words, increased membrane durability may also result in increased catalyst stability. Finally, chemical stability of hydrocarbon membranes will be considered in light of the advances over the last two decades in understanding PFSA stability. Similarities and differences will be discussed between these two classes of PEM membrane with suggestions on how the techniques used to understand PFSA stability could be applied to hydrocarbon ionomers and advance the understanding of chemical stability in these systems.
[1] Cullen, D. A.; Neyerlin, K. C.; Ahluwalia, R. K.; Mukundan, R.; More, K. L.; Borup, R. L.; Weber, A. Z.; Myers, D. J.; Kusoglu, A. New Roads and Challenges for Fuel Cells in Heavy-Duty Transportation. Nat Energy
2021, 6 (5), 462–474. .
[2] Curtin, D. E.; Lousenberg, R. D.; Henry, T. J.; Tangeman, P. C.; Tisack, M. E. Advanced Materials for Improved PEMFC Performance and Life. Journal of Power Sources
2004, 131 (1), 41–48.
[3] Coms, F. D. The Chemistry of Fuel Cell Membrane Chemical Degradation. ECS Trans.
2008, 16 (2), 235.
[4] Frey, M. H., Pierpont, D. M., Hamrock, S. J., US 8,367,267 and US 9,431,670
[5] Coms, F. D.; Liu, H.; Owejan, J. E. Mitigation of Perfluorosulfonic Acid Membrane Chemical Degradation Using Cerium and Manganese Ions. ECS Trans.
2008, 16 (2), 1735.
[6] European Chemicals Agency (ECHA) proposal submitted 7th February 2023
(Invited) Correlation of Exciton and Charge Carrier Dynamics with the Performance of Metal Halide Perovskite Solar Cells
Authors: Tachibana Yasuhiro 
Published: February 2024

Perovskite solar cells have been recognized as a newly emerging solar cell with the potential of achieving high efficiency with a low cost fabrication process. In particular, facile solution processed cell fabrication facilitated rapid development of optimum cell structure and composition. Over the last few years, the cell efficiency has exceeded 25%.
Highly efficient charge transfer reactions in addition to high charge separation efficiency and swift charge transport with minimum charge recombination are required to improve solar cell performance. Intensive studies have been focused on monitoring photo-induced exciton formation and charge dissociation, charge transport and interfacial charge transfer dynamics including interfacial charge recombination in perovskite solar cells.[1-5] Several parameters have been identified to influence these charge carrier dynamics, and therefore the solar cell performance.[1-5] Clarifying these parameters is extremely important to understand the charge transfer mechanisms to further improve solar cell performance.
In this presentation, we will present parameters controlling charge dissociation in metal halide perovskites and their charge separation and recombination dynamics at the perovskite interfaces employing a series of transient absorption and emission spectroscopies. Correlation of the key parameters controlling the exciton and charge carrier dynamics with the solar cell performance will be discussed [1-5].
This work was partly supported by JSPS KAKENHI Grant (19H02813) and (22H02182), and the Collaborative Research Program of Institute for Chemical Research, Kyoto University (grant number 2023-45 and 2022-99), Japan. We would like to acknowledge supports from the Australia-Japan Foundation for the international collaborative project. We also acknowledge supports from ARC LIEF fund (LE200100051 and LE170100235), Australia and School of Engineering in RMIT University, and Forefront Research Center, Faculty of Science at Osaka University.

References

[1] S. Makuta, M. Liu, M. Endo, H. Nishimura,A. Wakamiya and Y. Tachibana, Chem. Commun., 52 (2016) 673 - 676.
[2] M. Liu, M. Endo, A. Shimazaki,A. Wakamiya and Y. Tachibana, J. Photopolym. Sci. Technol.
30 (2017) 577-582.
[3] M. Liu, M. Endo, A. Shimazaki,A. Wakamiya and Y. Tachibana, J. Photopolym. Sci. Technol., 31 (2018) 633-642.
[4] M. Liu, M. Endo, A. Shimazaki,A. Wakamiya and Y. Tachibana, ACS Appl. Energy Mater., 1 (2018) 3722-3732.
[5] M. Liu, H. Liu, S. R. Padmaperuma, M. Endo, A. Shimazaki,A. Wakamiya and Y. Tachibana, J. Photopolym. Sci. Technol., 32 (2019) 727-733.
Effect of the Magnetostriction Induced on the Crystalline Structure of Nanoparticulate TiO2 Photoanodes and Their Relationship with the Photovoltaic Response of Black-Dye Sensitized Solar Cells
Authors: Valdez Nava Jesus Israel , Pérez-Nava Isa Fernanda , Bustos Erika , García-Melo José Alberto , Manriquez Juan 
Published: February 2024

The study of ferromagnetism (FM) in semiconductor oxides having non-cubic crystalline structures (e.g. TiO2) is attractive due to their applications in spintronics [1]. FM can be activated in TiO2 nanomaterials by promoting oxygen vacancies (VO) located in paramagnetic defected sites Ti3+VOTi4+. In this context, the VO can induce in Ti3+-doped TiO2 structures remarkable magnetic anisotropy energy (MAE) of 6.51x106 erg/cm3, thus indicating the magnetic saturation (Ms) should be achieved by applying external magnetic fields (MFs) of ~425 gauss [2,3]. Therefore, magnetostriction can be observed in ferromagnetic TiO2 films containing Ti3+VOTi4+ sites as a phenomenon in which their dimensions and shapes are changed when they are magnetized. In this work, black dye-sensitized solar cells (BD-SSC) were prepared using TiO2 nanoparticle films enriched by Ti3+VOTi4+ sites, to gain an understanding of the effects of magnetostriction on the photovoltaic responses of BD-SSC. In this way, photocurrent density-cell potential plots were obtained for the BD-SSC in the absence and presence of MFs having intensities of 125, 250, 500, 1000, and 2000 gauss. MFs lines were parallel applied to the surface of the BD-sensitized TiO2 photoanodes. Our results indicated that the photogenerated electron transport through the dyed TiO2 photoanodes was not limited by electron transfer to I3
- anions at the electrolyte in the absence or the presence of MFs, because all the values for the open-circuit potential (-Eoc
~ 0.553±0.014 V) remain constant. On the contrary, the obtained values for the short-circuit current density Jsc
and the global conversion efficiency, revealed that both parameters increased as a function of the MFs intensities, thus indicating that the magnetic lines were responsible for decreasing the degree of disorder (0<b<1) of the electron-traps at the intra-bandgap state's distribution of the TiO2 film (Jsc
is proportional to Q1/
b where Q is the number of trapped electrons) [4,5].
[1] M. Stiller et al., Front. Phys., 11(2023)1124924.; [2] D. Kim et al., J. Phys.: Condens. Matter, 21(2009)195405.; [3] B. Shao et al., J. Appl. Phys., 115(2014)17A915. [4] N. Kopidakis et al., J. Phys. Chem. B, 107(2003)11307. [5] J. van de Lagemaat et al., J. Phys. Chem. B, 104(2000)4292.

Acknowledgements

The authors thank the National Council for Science and Technology (CONACyT) Mexico for the funding support (grants CB No. 258789 and FOINS No. 3838). JIVN thanks CONACyT for his doctoral fellowship support (grant No. 893260).
The Nanostructured Future of Electrolytes
Authors: Mariani Alessandro , Liu Xu , Han Jin , Varzi Alberto , Passerini Stefano 
Published: February 2024

Lithium-ion and lithium-metal batteries with cobalt-free high-energy cathodes, as well as the newly emerging batteries employing post-lithium ions as charge carriers, are a few topics tackled in recent years for the development of batteries with higher energy density, lower cost, and improved sustainability. While all of them could (and will) be improved over time, electrolytes are prominent because of their ease of adapting to current technologies. Conventional organic electrolytes are usually flammable, toxic, and harmful to humans and the environment. For these reasons, over the years, several alternatives have been proposed. Ionic Liquids1 are promising from a safety point of view, being non-volatile and non-flammable, but they are usually fluorinated to meet specific performance standards. Another sustainable and cost-efficient approach is represented by the Water-in-salt electrolytes (WiSEs)2,3, given that the used salt is sustainable itself. Finally, the newest approach is to tackle the solubility properties of salts to obtain locally concentrated electrolytes using non-solvating solvents4. For all of the proposed new technologies, their impressive properties seem to emerge from the peculiar structural organizations of the species in the system. Therefore, employing experimental (SAXS and Raman) and computational (MD and DFT) techniques to comprehensively understand how the chemical species interact in such systems, is mandatory to further progress in the research.
Figure 1: a) Snapshot of the simulation box of a Locally Concentrated electrolyte. The ionic liquid comprise the worm-like structures, the solvent is only depicted on the left side as a transparent medium. b) coordination numbers as a function of salt concentration in a Water-in-salt electrolyte. c) X-ray scattering patterns for ionic liquid electrolytes and locally concentrated ionic liquid electrolytes at two different temperatures (20 °C top, and -20 °C bottom).
References
1 J. S. Wilkes, A short history of ionic liquids—from molten salts to neoteric solvents, Green Chemistry, 2002, 4, 73–80.
2 L. Suo, F. Han, X. Fan, H. Liu, K. Xu and C. Wang, ‘water-in-Salt’ electrolytes enable green and safe Li-ion batteries for large scale electric energy storage applications, J Mater Chem A Mater, 2016, 4, 6639–6644.
3 J. Han, A. Mariani, S. Passerini and A. Varzi, Energy Environ Sci, 2023, https://doi.org/10.1039/D2EE03682G
4 X. Liu, A. Mariani, H. Adenusi and S. Passerini, Angewandte Chemie - International Edition, 2023,https://doi.org/10.1002/ange.202219318.

Figure 1
How Reference Electrodes Improve Our Understanding of Degradation Processes in Half and Full-Cell KIB Setups
Authors: Panasenko Iurii , Jeschull Fabian 
Published: February 2024

For the last decade, the search for suitable alternatives for Li-ion batteries (LIBs) has steeply increased. While elements such as lithium and cobalt, are in high demand for LIBs, they could soon be replaced by less costly and more abundant elements1. One attractive alternative is potassium-ion batteries (KIBs) because of the abundance of potassium resources, and the lower standard electrode potential of K/K+ compared to lithium2.
For characterization of KIB materials can be used same approaches as for LIB. An exception to that is describing electrochemical behavior, especially in a half-cell. One of the most important challenges for KIBs is a reliable 3-el setup with a stable and reproducible reference electrode (RE). Without a RE, the only possibility to independently quantify the anode and/or cathode impedance is the disassembly of multiple cells and the recombination of the identical anode or cathode pairs in symmetrical cells3. While using a metallic reference electrode is a practical solution for LIBs (using Li metal), the high reactivity of K renders the metal unsuitable as a reference electrode in KIBs.
In this study, we outline our research on stable and reliable reference electrodes and compare several established approaches, specifically K-metal, a partially discharged Prussian white (K2Fe[Fe(CN)6]) and a more classic Ag/AgCl redox couple. Except for battery research, Ag|AgCIsat REs are commonly used in non-aqueous media in electrochemistry and offer the advantage of comparatively high chemical inertness, unlike K-metal or cathode-type RE. It was found that the evolution of degradation products from K-metal also induced significant drifts on a partly charged cathode RE (Fig. a), thus excluding both as reliable RE systems.
In our revised cell design, the Ag|AgCIsat reference electrode was integrated into a thin-layer battery compartment. With this 3-electrode configuration half and full cell experiments, previous 2-electrode tests were revisited. So, the only way to compare the behavior of electrodes in half in full is to have stable and chemically passive RE which is Ag/AgCl. With this setup we were able to study the impact of electrolyte additives on the electrode reactions in more detail and pinpoint cut-off limits in graphite/ K2Fe[Fe(CN)6]. For example, in our experiments it was observed how graphite electrodes degrade under the influence of the DTD (1,3,2-Dioxathiolane 2,2-Dioxide) additive(Fig b).
References:

Komaba, S., Hasegawa, T., Dahbi, M. & Kubota, K. Electrochem. commun.
60, 172–175 (2015).

Kubota, K., Dahbi, M., Hosaka, T., Kumakura, S. & Komaba, S. Chem. Rec.
18, 459–479 (2018).

Linsenmann, F., Pritzl, D. & Gasteiger, H. A. A J. Electrochem.
Soc.
166, A3668–A3674 (2019).

Costard, J., Ender, M., Weiss, M. & Ivers-Tiffée, E.. J. Electrochem. Soc.
164, A80–A87 (2017).

Figure 1
(Invited) Pt-Modified Aluminide Coatings for Ni-Base Single Crystal Superalloy
Authors: Jiang Yiming , Li Shuai , Liu He , Bao Zebin , Zhu Shenglong , Wang Fuhui 
Published: February 2024

Single phase (Ni,Pt)Al coating has been widely employed as state-of-the-art bondcoat for protecting hot-sectional components in commercial aero engines, especially for the parts made of Ni-base single crystal (SX) superalloys. For high temperature protective coating serving on SX superalloy, two interfaces are vitally essential for acquiring reliably long service life: the interface growing thermally-grown oxide (TGO) and the interface connecting coating and substrate alloy.
Normally, the excellent performance of PtAl coating derives from high Al content and the incorporation of Pt, which ensures formation of exclusively adherent oxide scale, α-Al2O3. To further improve the performance of Pt-modified aluminide coating, in present study reactive elements are introduced using co-electroplating method. Compared with singular doping, co-doping of Hf-Y demonstrated superior oxidation resistance. The oxide scale growth rate and spallation tendency of Hf-Y co-doped (Ni,Pt)Al coating were much smaller, as well as the surface rumpling extent. Besides, the grain size of Hf-Y co-doped (Ni,Pt)Al coating was finer than that of Hf- or Y- doped coatings in as-received state, indicating the capability of grain refinement. With the benefits of RE co-doping, the desirably thin/smooth TGO is thus accessible for Pt-modified aluminide coatings.
The other issue is the element interdiffusion at high temperature, which would affect the mechanical property of SX superalloy. According to Fick′s law of diffusion,
J

Al

= -
D

Al

·
δμ

Al

/

δ

x

,to reduce diffusion coefficient (
D

Al

) or chemical potential (
δμ

Al

/

δ

x

) would both decrease the diffusion extent (
J

Al

). Therefore, two strategies are employed: adding a diffusion barrier between coating and substrate, or designing a γʹ-PtAl coating. The performance of these modified aluminide coatings are evaluated in high temperature oxidation test. At last, doping behavior of some elements were explained by First-Principle Calculations.