bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microporous Polymer Membranes Enable Efficient Redox Flow Batteries for Energy Storage
Authors: Wong Tobias , Song Qilei 
Published: December 2024

Redox flow batteries (RFBs) are promising technologies for grid-scale storage of renewable but intermittent energy sources. RFBs offer superior lifetimes, design modularity and the ability to decouple power from capacity. Ion exchange membranes are critical components in RFBs. Their function is to minimize the crossover of redox active species whilst allowing fast conduction of charge-balancing ions. Perfluorosulfonic acid polymers, such as Nafion, are expensive ($500/m2) and produced using environmentally harmful polyfluoroalkyl substances (PFAS), which is seen as a key limitation in the widespread commercialisation of RFBs.
To overcome the challenges of high cost and low ionic selectivity posed by Nafion membranes, we replaced the phenyl groups in poly (ether ether ketone) (PEEK) with the bridged bicyclic triptycene moiety to introduce free-volume into the polymer matrix based on our previous work.1,2 Sulfonated PEEK polymers with triptycene backbones (sPEEK-Trip) were readily cast into mechanically robust membranes. Membrane structural and physical properties were characterized with a variety of techniques, elucidating the changes in water channel morphology. Ionic conductivity and ionic selectivity are critical parameters in flow batteries. Ionic selectivity determines the lifetime of the battery, where capacity is determined by the quanitity of redox species in the respective half-cells. The membranes were used in a range of flow battery chemistries, including aqueous organic flow batteries and alkaline zinc-iron flow batteries. Computational modelling was performed to study the fundamental polymer structures and ion transport mechanism. High ionic conductivity enables low resistance which enables higher efficiencies and cost reductions. However, increasing the ionic conductivity often results in a selectivity penalty owing to higher membrane swelling endowed by the higher hydrophilicity. sPEEK-Trip membranes have higher ionic conductivities (20.1 mS cm-1 vs 10.5 mS cm-1 in 1 M KCl) at the same ion exchange capacity and show no increase in redox species permeability (10-9 cm2 s-1). The measured redox flow battery performance surpasses all reported membranes in a neutral pH aqueous organic and an alkaline zinc-iron system.3 The energy efficiency beyond current densities of 200 mA cm-2 exceeded all reported membranes in the alkaline 2,6-DHAQ AORFB. Furthermore, a power density of 2.5 W cm-2 was achieved in the alkaline zinc-iron system, with an energy efficiency of 62% at current density of 500 mA cm-2. The membrane design will inspire the development of high-performance ion exchange membranes for electrochemical energy storage and conversion.

References

[1] Ye, C. et al. Nat. Commun.
2022, 13.
[2] Ye, C. et al. Angew.
2022, 134.
[3] Wong, T. et al. Joule, 2024, under review.

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Electrical Characterization of Metal Contacts to Carbon Nanostructured Materials
Authors: Sun Zewen , Cho Minsu , Nahar Arijun , Sankaran Kamatchi Jothiramalingam , Kato Yoshimine , Teii Kungen 
Published: December 2024

Among many types of nanostructured carbon materials, carbon nanowalls (CNWs) are the unique continuous structure of multi-layer graphene, which stands on a substrate surface almost vertically. Due to the high aspect ratio, high in-plane continuity, and large surface area, there are a variety of potential applications such as electron field emitters, electrodes of lithium-ion batteries, and gas sensors. In these applications, possible electrical resistance between metal electrodes and CNWs affects the resulting device performance. However, electrical contact behavior between metal electrodes and CNWs has not been reported. In this study, the effect of several metal species on contacts to nitrogen-incorporated CNWs is examined at temperatures from room temperature to 300 ºC.
Nitrogen-incorporated CNWs were deposited on quartz substrates by microwave plasma-enhanced CVD and followed by deposition of an array of electrodes of several metal species by sputtering or vacuum evaporation. The total resistance between pairs of electrodes were measured at temperatures between room temperature and 300 °C in a vacuum. The current-voltage characteristics for pairs of electrodes showed that all kinds of electrode materials produced straight lines, typical of Ohmic contacts, at low applied voltages. The contact resistance derived from the linear relation between the total resistance and the distance between electrodes decreased gently with increasing temperature, indicating low conduction barriers [1]. Consequently, the measured contact resistance could account for a large portion of the total resistance. The measured result for nanocrystalline diamond will also be reported.
[1] Z. Sun, M. Cho, L. Huang, R. Hijiya, Y. Kato, K. Teii, ECS J. Solid State Sci. Technol. 11, 61012 (2022).
Investigating Stress-Induced Geometry Effects on Corrosion Rates of Stainless Steel in Aqueous Solutions
Authors: Murphy Alexandra , Yapell David , Troy Lyra , Allen Jabari , Ruiz Christian , Dumont Joseph , Rockward Tommy 
Published: December 2024

Select type of Stainless Steel (SS) are widely used throughout a vast number of critical sectors and technologies due to their corrosion resistance and good mechanical properties. Throughout the manufacturing process the shaping of SS can introduce microstructural stresses that may lead to localized corrosion. Most corrosion mitigating techniques require a protective coating(s) or surface treatment techniques. Structural changes introduced in the manufacturing process can damage the interfacial layers and impact corrosion rates. Traditional corrosion measuring techniques typically require a flat surface and thus cannot be directly used to study curved materials. The advent of additive manufacturing has allowed for new designs previously unachievable with traditional manufacturing techniques.
In this study, custom additively manufactured holders are developed to analyze the effects of curvature in stainless steels using traditional electrochemical techniques. The impact of the degree of curvature will be compared to flat samples using the same material. Corrosion rates and mechanisms are analyzed using electrochemical techniques, such as potentiostatic, potentiodyanmic, electrochemical impedance spectroscopy, and complemented by scanning electron microscopy and profilometry.
(Invited) Vacuum-Processable Additive for Controlling Growth of Perovskite Crystals in All Vacuum Processed Perovskite Solar Cell
Authors: Kim Kyungkon 
Published: December 2024

We present a novel method for controlling the growth of perovskite crystals in a vacuum thermal evaporation process by utilizing a vacuum-processable additive, propylene urea (PU). Co-evaporating of perovskite precursors and PU retards the direct reaction between the perovskite precursors. This facilitates larger domain size and reduced defect density.
In this study, we present a novel method for controlling the growth of perovskite crystals in a vacuum thermal evaporation process by utilizing a vacuum-processable additive, propylene urea (PU). By co-evaporating perovskite precursors with PU to form the perovskite layer (Figure1), PU, acting as a Lewis base additive, retards the direct reaction between the perovskite precursors. This facilitates larger domain size and reduced defect density (Figure 2). Following the removal of the residual additive, the perovskite layer, exhibiting improved crystallinity, demonstrates reduced charge recombination, as confirmed by time-resolved microwave conductivity analysis. Consequently, there is a notable enhancement in open-circuit voltage and power conversion efficiency, increasing from 1.05 V to 1.15 V and from 17.17% to 18.31%, respectively. The incorporation of a vacuum-processable and removable Lewis’s base additive into the fabrication of vacuum-processed perovskite solar cells offers new avenues for optimizing these devices.

Figure 1
(Invited) Integration of Sulfide and Halide Based Solid Electrolytes in All Solid State Batteries
Authors: Nanda Jagjit 
Published: December 2024

Lithium-metal based solid-state batteries (SSB) are considered to be the holy-grail of the next generation battery technology with promising energy density (500 Wh/Kg) and safety. It also provide a flexible platform for integrating a number of promising solid-electrolytes (SEs) with high capacity cathodes using either, a thin lithium metal, or anode-less configuration. The talk will focus on the design and processing of high capacity SSBs using thin Argyrodite (LiPS5X; X= Cl, Br) based SE separator and halide based (LiYCl3) catholyte. Utilizing halide catholyte, NMC 811 cathodes can be cycled upto 4.4 V and providing much higher capacity and stability compared to pure Argyrodite based SE. For example, compared to sulfideSE, halide based catholyte SSB (i) delivers 20% higher capacity at the same rate, (ii) exhibit higher 1st cycle coulombic efficiency (93 vs.74%), (iii) enables longer cycling stability (150 vs. 50 cycles) and (iv) shows lower overpotential due to less CEI formation. Further, we study the effect of stack pressure on the cycling stability. Increasing stack pressure 2 to 14 MPa, allows better solid-solid contact enabling better cycling stability and capacity retention. The performance deteriorates when the pressure is larger 20 MPa, possibly due to the Li metal creeping at the anode side. Capacity fading mechanism is investigated using scanning electron microscopy and x-ray synchrotron microscopy and spectroscopy.
Acknowledgement
This research is supported by Asst. Secretary, Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (VTO), through the Advanced Battery Materials Research (BMR) Program.
Development of 3D Printing Electroplating Tooling Assisted By Multiphysics Modeling
Authors: Fedi Baptiste , Boucher Aurélien , Schoenleber Jonathan 
Published: December 2024

The electroplating industry faces significant challenges in terms of coating performance and quality. The use of multiphysics simulations offers a promising approach to address these challenges.
This conference highlights the use of multiphysics modelling, including current distribution and computational fluid dynamics (CFD), in the development of 3D printing innovative tooling systems for electroplating processes. The study emphasizes the role of simulation in optimizing the electroplating process, focusing on thickness distribution, efficiency, and coating composition.
Electroplating complex geometry can be challenging due to the heterogenous current distribution. By modelling the distribution of the electrical field in the electrolyte bath, we can obtain a better understanding of the electrochemical phenomena that occur during the electroplating process. This allows for the identification of areas with low or high current density. Using this results can help to design a computer-aided specific tool, to reduce edge effects and increase current intensity in areas where the throwing power of the bath is insufficient.
Coating quality and uniformity also depend of agitation due to the renewability of ion and additives, and the elimination of hydrogen production. In order to take into account this contribution, computational fluid dynamics (CFD) is employed to study the movement of the electrolyte fluid within the electroplating system. By analysing fluid velocity, tool design can be optimized to consider the flow, minimizing disturbances and improve species renewability in confined aeras, such as holes or cylinders.
The multiphysics approach also enables the evaluation of the impact of operational parameters on coating composition like Zn-Ni.
The use of innovative multiphysics modeling of industrial electrochemical processes allows for the design, aided by computation, of very complex and non-conventional tooling concept. In order to create these complex tools, we are using 3D printing by combination of multiples materials. Polymers and elastomers are used for shielding and masking, while metal 3D printing electrodes is employed to create auxiliary anodes and current rubbers.
Dispersibility and Morphologically Controlled Synthesis Method of Fe Metal Particles By Utilizing the Metal Complexes in an Aqueous Solution
Authors: Takahashi Hideyuki , Yokoyama Koji , Kumon Shoichi , Sato Kimitaka , Yokoyama Shun 
Published: December 2024

Fe oxide based magnetic beads are widely used to recover the virus in an immunoprecipitation process. Moreover, these can also apply for using as the toxic metal ions recovery materials. To increasing these abilities, in other word, to synthesize the high-performance magnetic beads, the use of pure iron particles with a diameter of 1 µm as the core materials are effective.
Thus, the development of effective and green synthesis method of Fe particles in an aqueous phase is important. However, in an aqueous phase synthesis process, Fe particles were synthesized only in acidic solution by using strong reducing reagent, such as NaBH4, while it cannot be achieved in the basic solution since iron hydroxide, which is easily formed in this condition, cannot be reduced into metal Fe. Here, former method is not suitable for commercial synthesis procedure since large amounts of Hydrogen gas generated. Therefore, synthesis method of Fe iron particles under basic condition should be developed.
Until now, we tried to synthesis the various metal/alloy nanoparticles, such as Pd20Te7 nanoparticles for the catalysts and Cu-In alloy nanoparticles for the application of solar cell, by utilizing the restricted metallic complexes controlling method in an aqueous solution under room temperature. In this method, reduction potential of the metal species can be controlled under the room temperature, consequently metal/alloy nanomaterials with uniform and well crystallized structure can be successfully synthesized.
In this study, we proposed the dispersibility and morphologically controlled synthesis method of Fe particles under basic conditions and using gel networks which is a safe and simple approach to suppress the synthesis of chain-type morphology.
Fe complex ratio in an aqueous phase were restricted as the function of pH, complexing reagent species and/also concentration. For example, Fe complex can be restricted into single complex in the basic condition, 8<pH<11.
By using this homogeneous Fe complex condition, metal Fe nanoparticles were successfully synthesized. Moreover, the addition of gel networks can effectively control the dispersibility of the synthesis Fe particles. Removing method of gel networks on the surface of the synthesized Fe particles are also developed, and finally Fe particles with the organic-free surface can be obtained.
Other results will present in our presentation. This work was supported by JSPS KAKENHI Grant Number 21H03628 and DOWA holdings.
[1] H. Takahashi et.,al, Applied Catalysis A: General 392 (2011) 80–85
Large-Scale Production of Nanotube Silicon for Lithium-Ion Batteries
Authors: Manwaring Kyle Charles , Gonda Brian , Parise Cale , Garcia Lizbeth Zurita , Sun Fei , Adhikari Kobit , Wheeler Dean , Mazzeo Brian A. 
Published: December 2024

Silicon’s relatively high energy density in comparison to the more common anode material, graphite (3580 mA h g-1
for silicon compared to 371 mA h g-1
for graphite) has made silicon an intriguing anode material for lithium-ion batteries. However, during lithiation, the volume of silicon increases by approximately 300% causing irreversible capacity loss. During the initial charging of an anode, a solid electrolyte interface (SEI) forms on the surface of the anode. The formation of the SEI consumes lithium, resulting in irreversible capacity loss. The large volume expansion of silicon can break the SEI layer. This results in a new SEI layer needing to be formed and further irreversible capacity loss. In addition, the expansion of the silicon particles can lead to silicon particles being isolated from the anode where they can no longer participate in the charging and discharging process, lowering the capacity of the anode. To accommodate for this large volume expansion, silicon nanoparticles on the scale of 50 microns are often used to accommodate for the large volume expansion and help retain capacity. Silicon nanotubes provide additional benefits such as increased structural stability, faster lithium-ion diffusion, and greater electrical conductivity than silicon nanoparticles.
This work details a process to produce silicon nanotubes from halloysite on a large scale. Halloysite is an alumina-silica-based structure composed of natural nanotubes. Silicon can be obtained from halloysite by etching off the alumina components and further reducing the silica to silicon through a magnesiothermic reduction. However, both the etching step and reducing step are very exothermic. If the heat transfer is not controlled correctly, the heat released during these reactions can destroy the natural tube structure. The reaction temperature is dependent on a variety of variables including: reactor temperature, ramp rate, addition of salts, and quantity of reactants. The processes and parameters used to successfully manage the heat released as a part of scale up this process are described. BET and SEM imaging were used to determine the surface area and structure of the produced silicon. In addition, the electrochemical performance of the silicon was tested and investigated in patch cells.

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(Invited) EIS Measurements in Ionic Liquids: Monitoring of the Electrodeposition of a Thin Metal Layer
Authors: Kurchavova Ekaterina , Xie Yuelin , Vivier Vincent , Turmine Mireille 
Published: December 2024

Ionic liquids are increasingly used in a variety of applications, including electrolytes for electrochemical devices, solvents for the electroplating of thin metal layers, and corrosion inhibitors. Ionic liquids are a broad family of solvents whose physicochemical properties (viscosity, conductivity, etc.) depend on the nature of the anion and cation that form them. Some are protic with a labile proton, others are non-protic. Electrodeposition of metal in a protic ionic liquid such as ethylammonium nitrate (EAN) can be carried out at ambient temperature whereas higher temperatures are frequently performed in a non-protic ionic liquid. In addition, the electrodeposition of several elements is simple, yielding to an alloy whose composition and morphology are determined by the electroplating conditions. In this presentation, we will show how Electrochemical Impedance Spectroscopy (EIS) which is an efficient technique for characterizing the solid-liquid interface and investigating the electrodeposition mechanisms, can help for working in these media.
In a first part, we will look at the electrodeposition of Nickel, Cobalt and their mixtures in EAN, a pure protic ionic liquid, and discuss EIS results. In a second part, we will take advantage of the low vapor pressure of ILs, and we will discuss how we can characterize a material reactivity by performing electrochemical measurements in a 3 - 5 µL drop of ionic liquid.
(Invited) Faster ALD for Emerging Quantum Applications
Authors: Kurek Agnieszka , Besprozvannyy Dmytro , Saha Arpita , Shu Yi , Powell Michael , Lennon Ciaran , Knoops Harm 
Published: December 2024

Plasma Atomic Layer Deposition (ALD) enables the deposition of a wide variety of materials, with nanometre-scale resolution and precision. Self-limiting growth is a keystone characteristic of ALD processes but limits deposition rate. Long cycle times and low growth per cycle (GPC) impose practical limits on how thick ALD films can be grown. In the field of Quantum Technology (QT), superconducting nanolayers are required for use in Single-Photon Detectors (SPDs), superconducting qubits and interconnects for quantum computing.1 Some superconducting interconnects benefit from non-planar connectivity to control qubits,2 and 3D architectures are key for scaling larger arrays of qubits.3 The deposition of high-quality materials on high aspect ratio Through-Silicon Via (TSV) interconnects is essential but difficult to achieve by conventional sputter techniques. Superconducting nitrides in some QT applications demand relatively thick films (>50 nm), and this poses a new challenge for ALD: to maintain desirable film characteristics and grow thick layers much faster. Here we present recent developments from our new R&D ALD platform: PlasmaPro ASP.
The design of the remote, RF-driven plasma source has been optimised to deliver quick, repeatable plasma doses to the substrate with minimal plasma damage. The chamber size, pumping and precursor delivery have been carefully considered to enable efficient ALD of many materials. For multiple materials, we have demonstrated a reduction of cycle times. For example, rates of >25 nm/h for NbN and TiN which is about 3x faster than previously reported. Importantly, these materials retain excellent film properties. NbN showed excellent electrical resistivity (four-point probe), conformality (100% on 8:1 trench), and superconducting transition temperature (Tc) >11 K for <10 nm thick films – a key regime for SPDs. NbN and TiN crystallinity, film stress and film composition will be discussed. Furthermore, many other applications will benefit from this fast plasma ALD. We will also present plasma Al2O3 for power electronics which has been deposited on substrates of up to 200 mm in diameter with a less than one second ALD cycle time. As the needs of emerging quantum technologies and other applications change and continue to push process and film performance, production and research will benefit from high-quality, low damage, conformal films by fast, remote plasma ALD.
References:

Giustino et al., J. Phys. Mater. 3, 042006 (2021)

Kjaergaard et al., Annu. Rev. Condens. Matter Phys. 11, 369 (2020)

Yost, et al. npj Quantum Inf 6, 59 (2020)