bluuebunny/crossref_metadata_2025 huggingface dataset:
Unlocking BaTiO3 - SrTiO3 As Anodes for Highly Efficient and Stable Lithium-Ion Batteries
Authors: Oli Nischal , Sapkota Nawraj , Weiner Brad R , Morell Gerardo , Katiyar Ram S
Published: December 2024

Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds, namely barium titanate (BaTiO3) and strontium titanate (SrTiO3) nanoparticles, as anode materials for lithium-ion batteries from straight forward and simple carbonate-based electrolyte 1M LiPF6 (1:1 EC: DEC) with 10% Fluoroethylene carbonate. SrTiO3 and BaTiO3 electrodes delivered specific capacity of 80 mA h g-1 at a safe and low average working potential of ≈ 0.6 V vs Li/Li+ with excellent high-rate performance and long cycling of ~ 500 cycles at 100 mA g-1 current density. Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li+ storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries.

KEYWORDS: SrTiO3, BaTiO3, Perovskite, Lithium-ion batteries
A Catalytic Disproportionation Reaction of Polysulfides Enabled By a Bio-Carbon Host for Li-Sulfur Batteries
Authors: Qiu Dantong , Zheng Dong , Zhang Xiaoxiao , Qu Huainan , Ding Tianyao , Liu Miao , Qu Deyang
Published: December 2024

Lithium-sulfur (Li-S) batteries are regarded one of the promising alternatives of conventional lithium-ion (Li-ion) batteries because of its high theoretical energy density (2600 Wh kg-1), abundance resources on earth, and low cost of sulfur. Nevertheless, several significant challenges persist in the practical application of Li-S batteries, with the most urgent being the dissolved shuttle effect of long-chain lithium polysulfide (LiPS) species during cycling [1]. Using porous host material for sulfur cathode is one of the commonly applied strategies to physically prevent the diffusion of LiPS from diffusing toward lithium anode, and therefore inhibit the shuttle effect [2]. However, the weak Van der Waals forces is in sufficient to anchor the dissolved LiPS because the non-polar surface of carbon material is unable to bind polar and ionic polysulfide ions. Introducing heteroatoms into the host materials is a way to enhancing anchoring of PS at cathode side [3]. In our previous research, we reported a novel carbon host (denoted as NC) for sulfur cathode from natural silk [4]. The obtained carbon host presented excellent cycling performance because of its hierarchical porous structures and nitrogen-contained functional group. In addition, we found the carbon has the ability to catalyst the disproportionation reactions of PS, accelerating the conversion of PS ions into solid products of elemental sulfur (S8) and lithium sulfide (Li2S2) serves to minimize the residence time of PS ions in the electrolyte. In this study, we proposed a hypothesis of a catalytic pseudo-8-electron redox reaction of S/NC cathode and analysis the process using high-performance liquid chromatograph (HPLC) analysis and electrochemical characterizations.

[1] Zhang, S. S. (2013). Liquid electrolyte lithium/sulfur battery: Fundamental chemistry, problems, and solutions. Journal of Power Sources, 231, 153-162.

[2] Ye, H., Yin, Y. X., Xin, S., & Guo, Y. G. (2013). Tuning the porous structure of carbon hosts for loading sulfur toward long lifespan cathode materials for Li–S batteries. Journal of Materials Chemistry A, 1(22), 6602-6608.

[3] Song, J., Xu, T., Gordin, M. L., Zhu, P., Lv, D., Jiang, Y. B., ... & Wang, D. (2014). Nitrogen‐doped mesoporous carbon promoted chemical adsorption of sulfur and fabrication of high‐areal‐capacity sulfur cathode with exceptional cycling stability for lithium‐sulfur batteries. Advanced functional materials, 24(9), 1243-1250.

[4] Qiu, D., Zhang, X., Zheng, D., Ji, W., Ding, T., Qu, H., ... & Qu, D. (2023). High-performance Li-S batteries with a minimum shuttle effect: disproportionation of dissolved polysulfide to elemental sulfur catalyzed by a bifunctional carbon host. ACS Applied Materials & Interfaces, 15(30), 36250-36261
Structural Modification Effects on Organic Polymer Nano-Photocatalyst Performance for Hydrogen Evolution
Authors: KIM Taek MIN , An Sanghyeok , Kim Junho , Ham Gayoung , Jung In Hwan , Cha Hyojung , Chung Dae Sung
Published: December 2024

Photocatalytic reactions provide a pathway to completely break down water and produce sustainable, renewable fuels. The use of organic materials in fabricating photocatalytic nanoparticles is particularly promising due to their ability to absorb a wide range of light, including visible and near-infrared spectra, and their potential for enhanced performance through adjustments of conjugated structure or side chain. This study explores the fabrication of nanoparticle photocatalysts from organic materials aimed at generating hydrogen via an oxidation-reduction process. Our focus is on examining how structural modifications of polymers with donor-acceptor backbones influence their photocatalytic efficiency. Through a series of spectroscopic experiments and theoretical insights, we conducted a thorough analysis of these structural variations in organic polymers. The results confirm that PFTz, featuring a thiophene structure, outperforms PFBTz in several key aspects. This study underscores the importance of precisely modifying organic photocatalytic nanoparticles, suggesting that such modifications can significantly enhance performance compared to current methods.
Achieving Superior Li-O2 Battery Performance through Controlled Formation of Discharge Products within MOF/rGO Structures
Authors: Kang Shin Joon , Jeong Hyung Mo
Published: December 2024

Electrochemical energy storage systems (ESSs) are crucial for various applications, such as portable electronics, transportation vehicles, and large-scale grid systems. This is evident from the significant increase in social demand and market share over the past few decades. Li-O2 batteries (LOBs) have the highest theoretical capacity among current batteries, but their capacities degrade significantly over charging–discharging cycles due to the irreversible growth/decomposition of Li2O2 products in the positive electrodes. This degradation is due to low round-trip efficiency, slow rate capability, and poor cycle stability, caused by the sluggish dynamics of the oxygen reduction and evolution reactions (ORR/OER). Particularly, the uneven growth of Li2O2 nucleation sites in 3D structures and the high overpotential for Li2O2 breakdown during charging are major obstacles to achieving high capacity. In this study, we introduce a metal–organic frameworks (MOFs) with lithiophilic sites attached to reduced graphene oxide (MOF@rGO) as a positive electrode material to address this issue. The ordered 3D nanocages were shown to control the size and shape of Li2O2 growth over multiple charging-discharging cycles, indicating that N sites in MOF facilitate conformal Li2O2 formation inside MOF’s 3D nanocages during discharging. During charging, these N sites also allowed for the adequate decomposition of Li2O2 products within the 3D MOF nanocages. Conformal Li2O2 growth during discharging was promoted, while Li2O2 decomposition during charging occurred with a low overpotential (0.487 V vs. Li+/Li at 200 mA gc
-1), outperforming the Pt/C-based electrode (0.857 V). The MOF@rGO//Li LOBs demonstrated an exceptional discharge capacity (17,275 mAh gc
-1 at 100 mA gc
-1) and stable cycling for 270 cycles at 1,000 mAh gc
-1 under 2,000 mA gc
-1. Additionally, the high gravimetric capacity at low mass loadings (0.27-0.44 mg cm-2) and stable cycle operation at a high areal-current density (0.5 mA cm-2) highlight significant potential for practical applications.
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.

Figure 1
Approaching the Atomic Limit of Optically-and Electrically-Active Quasi-1D Van Der Waals Crystals Using Carbon and Boron Nitride Nanotube Encapsulation
Authors: Arguilla Maxx
Published: December 2024

The realization of stable monolayers from 2D van der Waals (vdW) solids has fueled the search for exfoliable crystals with even lower dimensionalities. To this end, 1D and quasi-1D (q-1D) liquid vdW crystals comprising weakly bound subnanometer-thick chains have been discovered and demonstrated to exhibit nascent physics in the bulk. Although established micromechanical and -phase exfoliation methods have been applied to access single isolated chains from bulk crystals, interchain vdW interactions with nonequivalent strengths have greatly hindered the ability to achieve uniform single isolated chains. In this talk, I will present how encapsulation of the model q-1D vdW pnictogen chalcogenide crystals (Sb2S3 and Sb2Se3) within single-walled carbon nanotubes (CNTs) and boron nitride nanotubes (BNNTs) circumvents the relatively stronger inter-chain vdW interactions between the chains. I will discuss in detail how this methodology allows for the isolation of few nanometer-thick chain bundles and sub-nanometer-thick single chains with structural integrity and crystalline order, as supported by a series of electron microscopy and optical spectroscopy data. Furthermore, I will describe how encapsulation of pnictogen chalcogenides within well-defined nanotubes lead to pronounced blue shift in the optical absorption edges from the near-infrared to the visible range due to quantum confinement effects. I will conclude the talk by briefly describing how the presence of nanoscale to sub-nanoscale defects or discontinuities along the guest-nanotube interface strongly influences the degree of crystalline order of encapsulated single chains and nanostructures. Altogether, the results that I will present serve to solidify the understanding of how q-1D vdW pnictogen chalcogenides crystallize within confined synthetic platforms, thereby opening opportunities in understanding dimension-dependent properties and potential optoelectronic device applications of a plethora of emergent 1D and q-1D vdW solids.
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).
Tailored Carbon Dots in Solar Energy Conversion Schemes
Authors: Guldi Dirk Michael
Published: December 2024

Addressing the dual challenge of meeting the world's escalating energy needs while simultaneously decreasing carbon dioxide emissions has emerged as a pivotal issue in the new millennium. The Statistical Review of World Energy's latest report by British Petroleum Company plc reveals that global power consumption was around 18.9 terawatts (TW) in 2021, with projections estimating a surge to 30 TW by 2050. In stark contrast, solar radiation delivers a 120,000 TW to the Earth's surface, a quantity that exceeds the projected energy consumption of 2050 by 4,000 times. Efficiently harnessing and storing this immense solar energy is increasingly seen as a viable route towards a sustainable energy network. A promising solution lies in carbon-based systems. Carbon dots (CDs), an emerging class of nanomaterials, show great potential in this field. These can be synthesized through scalable methods using various carbon and nitrogen precursors, including waste, making them both cost-effective and recyclable. CDs offer a range of photophysical properties, such as variable photoluminescence and the generation of spin-active states. Furthermore, CDs are biocompatible, non-toxic, and environmentally friendly. Unlike traditional binary semiconductors, their photocatalytic attributes can be finely adjusted using a variety of organic chemistry functionalization techniques. While CDs have primarily been optimized for PL properties, their application in metal-free photocatalysis remains largely untapped. Major obstacles are the large structural diversity and complex multicomponent arrangement of CDs, along with the high variability of their photoactive centers, presenting a unique challenge. The ongoing controversy over the exact CDs structure, further compounded by a limited understanding of how this structure influences their photophysical properties, significantly hinders advancements in CDs design. This challenge significantly hampers progress in the development of more effective CDs for solar-driven water-splitting, underscoring the urgent need for increased collaboration between experimentalists and theoreticians now more than ever. In this contribution, we delve into the current understanding of photocatalytically active CD-based systems. The focus is set on model systems that feature no co-catalysts. We explore the role of CDs, shed light on the structure-activity relationship and detail photon- and charge-management in the excited state. Additionally, we share our insights on the potential opportunities that emerge from a deeper comprehension of CDs.
Graphitic Engineered Carbon Supports for Fuel Cell and Electrolyzer Catalysts: Significance and Characterization Methodology
Authors: Payne Michael , Klein Molly , Lenhart Brian , McKinney Samuel , Hernandez Delia , Ostraat Michele
Published: December 2024

Interconnected mesoporous carbons are an integral support material for many fuel cell and electrolyzer electrode catalysts because of their conductivity, their structural tunability, and the abundance of carbon precursors. The structure and morphology of the carbon support have significant impacts on electrocatalyst performance and durability, and improvements to the synthesis and characterization of carbon supports will ultimately advance sustainable fuel cell and electrolyzer technologies towards widespread adoption. One essential aspect of the carbon structure is its “degree of graphitization,” or the proportion of sp2-hybridized crystalline graphite structures that comprise the solid carbon. Graphitization of solid carbon supports can improve their stability against oxidation and corrosion, ultimately improving the durability and thus catalyst lifetime of fuel cell and electrolyzer devices; as such, it is essential to have detailed methodologies, both quantitative and qualitative, to describe the “degree of graphitization” of carbon supports for performance optimization. Here, we discuss techniques for characterizing the degree of graphitization of solid carbons such as powder X-ray diffractometry (PXRD), Raman spectroscopy, and wide-angle X-ray scattering (WAXS), and apply these techniques to a new class of carbon materials developed by Pajarito Powder known as the Engineered Catalyst Support (ECS). ECS materials are mesoporous carbons with tunable mesopore structures and graphitization levels, allowing these techniques to be demonstrated across a related series of carbon materials. From this analysis, a recommended methodology is given for characterization of graphitic carbon supports in the context of fuel cell and electrolyzer technologies.
(Invited) Predictive Modeling of the Biological Fate of Nucleic Acid Nanotechnologies: Bridging In Vivo and in Vitro Analyses
Authors: Clark Heather A. , Eades Ciara , Ma Kristine , Langlois Nicole I
Published: December 2024

We work at the interface of chemistry and biology to develop and apply novel nanoscale probes for biological measurements. In order to fulfill our goal of chemical imaging deep in the body (brain, central nervous system, circulatory system) we are we are tailoring our probes to be compatible with advanced imaging techniques to image deep in the body. Ultimately, we will use the probes to image specific chemical processes and biomarkers in the brain/body, in real-time. A common material we use in our probes is nucleic acids, which is biocompatible and easily forms uniform nanostructures (nucleic acid nanotechnologies, NANs). One of the fundamental concerns of NANs for use in vivo are the degradation and clearance properties once in the body. Although the scientific community commonly uses in vitro techniques such as gel analysis after exposure to diluted enzymes, there is no established protocol that enables comparison of results across research groups or publications. Additionally, most analysis techniques take place in diluted serum and then is extrapolated to expected performance in the body. Here, we apply a distinctive ratiometric method of size exclusion chromatography (SEC) to study the stability of NANs by characterizing degradation from enzymes and human serum with a systematic approach to build a matrix of profiles. Furthermore, data analysis using a ratio chromatogram technique enables NAN peak deconvolution from the matrix of serum proteins and a quantitative analysis despite sample dilution. Thus, our technique does not require labeling of the NAN for analysis and can be performed with representative concentrations of human serum. We will discuss the method and demonstrate with examples of novel structures.
(Invited) Organic Catalysis Promotor for Accelerating Oxygen Evolution Reaction Toward Advanced Water Electrolysis
Authors: Lee Sechan , Lee CHangsoo , Kim MinJoong , Doo Gisu , Seo Myeongmin , Park Hyeonjung , Lee Yeonsoo , Yun Young Hwa , Kim Ik-Sun , Jung Hye Bin , Cho Hyun-Seok
Published: December 2024

As the concerns about energy and environmental issues rapidly increase, the requirements for developing renewable energy sources are highly demanded to achieve the carbon-neutrality by 2050. Among the suggested strategies for carbon neutrality, green hydrogen production via water electrolysis is treated as a promising breakthrough to alternate the currently used fossil fuel-based energy production since it utilizes clean and eco-friendly resources of water and electricity. However, there still remains a limitation of which mostly used noble metal-based catalyst materials such as iridium, and platinum result in severe carbon dioxide emission during production and recycling processes in addition to the extremely high cost and scarcity. Therefore, it is mandatory to minimize the noble metal contents in catalyst electrodes to ultimately reach carbon neutrality. Diverse approaches have been suggested to reduce the amount of noble metal contents such as developing non-noble metal catalysts and single-atom catalysts as well as designing electrode architecture for low loading on the support materials. Nonetheless, limited catalytic performances or increased process cost from suggested strategies still hinders the development of large-scale water electrolyzer. Herein, we suggest a novel concept of organic catalysis promotor as a strategy for minimizing noble metal contents in catalysts. Organic catalysis promotor as an additive in an electrolyte can enhance the hydrogen production efficiency with the spontaneous chemical interaction with the intermediate state of a catalyst during water electrolysis reaction, which can further result in reducing the required amount of noble metals for green hydrogen production. We developed the model organic catalysis promotor for oxygen evolution reaction in alkaline water electrolysis, and it successfully reduced overpotential of 70 mV at a current density of 100 mA cm-2 with only adding a slight amount of 1 mM organic catalysis promotor in KOH electrolyte. This catalysis promoting capability could be maintained even over a week, and the possibilities of further expansion of organic catalysis promotor material group and general applicability to representative oxygen evolution reaction catalysts were also proved. This novel concept of organic catalysis promotor has a great potential to be further expanded toward hydrogen evolution reaction promotion and acidic water electrolyzer. Furthermore, it can suggest a new breakthrough for the development of large-scale water electrolyzer with minimizing the noble metal contents in a sustainable and economical way.
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) High Performance Flexible Perovskite Solar Cells Employing UV-Sintered Electron Transport Layers
Authors: Ko Min Jae
Published: December 2024

Organic-Inorganic halide perovskites have emerged as a promising light absorbing materials for next-generation solar cells due to their extraordinary photoelectrical properties and appropriate bandgap energy, making them suitable for single- and multi-junction solar cells. A distinct advantage of perovskite is their ability to be easily deposited on any substrate at desired nanoscale thicknesses using a layer-by-layer method at room temperature. Such a facile and low-temperature process facilitates the fabrication of devices even on lightweight and flexible polymer-based substrates. To realize flexible solar cells on plastic substrates, all procedures must employ a low-temperature process, below 150°C, compatible with polymer substrates. However, n-type metal oxides traditionally used for electron transport layer (ETL) necessitate high-temperature thermal annealing to enhance crystallinity and interparticle connectivity. In this study, we propose UV sintering processed ETL preparation for high-performance flexible solar cells. The process involves synthesizing highly crystalline metal oxide nanocrystals stabilized with organic ligands, spin-coating their dispersion, followed by UV irradiation. The energy level of ETL is controlled by doping metal ion such as gallium to reduce the energy level mismatch with the perovskite. We demonstrate that a systemically designed ETL enhances the photovoltaic performance and mechanical stability of flexible optoelectronic devices.
(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
Flammability (Flash point) of Gel Polymer Electrolytes
Authors: St-Antoine Caroline , Foran Gabrielle , Prébé Arnaud , Ayme-Perrot David , Dolle Mickael
Published: December 2024

Gel polymer electrolytes offer a promising pathway for the rapid commercialization of next-generation batteries. These electrolytes are composed of a polymeric matrix in which a solvent is trapped. The liquid component provides high ionic conductivity and favorable interfacial properties , while the polymeric matrix enhances electrolyte safety by reducing flammability. Most of the flammability tests that are performed on gel polymer electrolytes are neither standardized nor quantitative. This makes it difficult to compare materials and evaluate the safety of different electrolyte components. Our group has confronted this issue by developing new methodology to quantify the flammability of gel polymer electrolytes by adapting flash point measurements to gel systems [1]. The methodology that was used to measure the flashpoint of gel polymer electrolytes is presented here. A series of gel polymer electrolytes are analyzed to determine how intermolecular interactions that are present in these systems influence the flash point temperature of the gel polymer electrolytes. The objective is to understand which factors influence flammability, and ultimately, how to achieve a balance between a high flash point and high ionic conductivity in these systems.

St-Antoine, C., et al., Relationship between the intermolecular interactions of carbonyl (PC) with nitrile (HNBR) functional groups and the flash point of a gel polymer electrolyte. Journal of Materials Chemistry A, 2023. 11(20): p. 10984-10992.
(Invited) Non-Intuitive Failure Mechanics in Solid State Batteries
Authors: Hatzell Kelsey
Published: December 2024

Solid electrolyte failure can occur through a range of different mechanisms. Electrochemical delamination at electrode and electrolyte interfaces is a prominent failure mechanism during high capacity and low N/P operating conditions, and filament formation is prevalent during high rate and long cycle-life deposition. Interface coherency and solid electrolyte microstructure both impact the ultimate degradation mode. Solid electrolyte microstructure, described in part by the density, periodicity, and interconnected arrangement of pores, plays a role in failure. Herein, we combine modeling, synchrotron imaging, and electrochemical experiments to systematically understand how densification and processing of solid electrolyte influences filament formation. The work reveals that the density of pores does not correlated with failure. Instead, the periodicity, size and arrangement of pores is a driver for failure in amorphous solid electrolytes absent of grain boundaries.
(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.
Thermodynamic and Economic Assessments of Electrochemical CO2 Conversion to Dimethyl Ether
Authors: Arndt Brenden , Nazemi Mohammadreza (Reza)
Published: December 2024

We carry out a techno-economic assessment to evaluate the viability of industrializing the electro-conversion of CO2 to various fuels including dimethyl ether, propane, and methane. The emphasis of this work is on dimethyl ether (DME) as it is considered a viable diesel alternative. There were four pathways to DME considered in this work. Two pathways used two electron transfer intermediates, carbon monoxide and formic acid, to methanol, then dehydration of methanol to DME. One pathway considered direct CO2 reduction to methanol then its dehydration to DME. And finally, a direct 12 electron reduction of CO2 to DME route was considered. Both routes to propane and methane were direct with 20 electrons and 8 electrons respectively. Operations and capital costs (OPEX and CAPEX respectively) were mainly considered and combined to generate a levelized cost of energy to compare to the market price of common fuels. The main conclusion drawn was OPEX dominates overall costs due to high currents, large overpotentials, and renewable electricity costs. The best route was found to be using 2 electron transfer intermediates due to their low overpotentials and higher selectivities. It was found that if under 2 cents per kWh for electricity along with a Faradaic efficiency of over 70% is achieved, then this process can match the 500 $/tonne market price of DME. Finally, a cost recovery model was demonstrated where hydrogen and oxygen are recovered via gas separation and water electrolysis respectively. If both products are either sold or reused to save money, then the production costs of these fuels decrease dramatically and become economically viable.

Figure 1
Electrolytic Silver Recovery from Photovoltaic Waste
Authors: Rassoolkhani Alan , Dunn Collin , Conner Ryan , Lippert Cameron , Landon James
Published: December 2024

As an increasing number of photovoltaic (PV) systems reach end of life, there is a growing need to develop a process to keep critical materials in the supply chain. Currently, the processing cost of recycling solar panels exceeds the value of raw materials being collected. While there are many ways to approach this problem, one standout method is to improve silver recovery efforts. Silver, which is used as the fingers on the front contact, makes up less than 1% of the total mass of decommissioned systems while constituting approximately 40% of the value of the raw materials. Mechanical separation techniques have been generally successful in extracting the silver, but the product is still low in concentration and recyclers encounter significant processing fees from off takers. In this talk, a chemical leaching process in conjunction with an electrochemical recovery system will be discussed as a means of extracting high purity silver from recycled PV materials. Classically, electroplating processes utilize solutions containing metals at concentrations >10 g/L. In this case, the expected concentrations are less than 2 g/L, and maintaining high yields will require the electrochemical device to operate at concentrations on the order of 100s of ppm. Mass transport limitations will be mitigated by the development of a flow-through 3D cathode architecture, which will allow the system to operate at lower concentrations without requiring the application of higher cell potentials that would decrease selectivity and subsequently lower the purity of the recovered silver product. The performance of these devices will be explored in conjunction with auxiliary system components and controls that will be integrated to yield an automated system for silver powder recovery.

Figure 1
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
Electrochemical Adsorption-Desorption Mechanism on Composite Electrode Materials for CO2 Direct Air Capturing
Authors: Kim Hyungjin , Han Kyeongwon , Park Hyeonji , Song Jeongeun , Lee Ganghui , Jeon Yukwon
Published: December 2024

Use of carbon-based fossil fuels, greenhouse gases are emitted to the atmosphere causing fatal environmental issues like global warming. To overcome this problem, Sustainable Development Goals (SDGs) is now a fundamental issue for worldwide nations. Among them, carbon neutrality stands as a central pillar since CO2 has the biggest portion of emitted green-house gases. Emitted CO2 from industrial facilities like factories and incinerators is collected by various carbon capturing technology which is developed due to the pursuit of carbon neutrality necessities. Among them, Direct Air Capture (DAC) is gaining interests due to its superior efficiency compared to other alternatives such as filters and absorbents for the challenges like high pressure and elevated temperatures at the CO2 capturing process. Furthermore, the durability of filtration materials and waste problems poses a significant concern to the environment. To overcome these limitations, electrochemical adsorption system is looking forward to becoming the next generation carbon capture technology. By applying varying electrical energies, this allows adsorption and desorption of CO2 within an adsorber layer. By this mechanism, we can significantly reduce the filtration waste of capturing process. The adsorber layer is consisted with catalysts, which has large surface area and active sites that can adsorb and desorb CO2 stably with electricity. Detailed physicochemical and electrochemical characterizations of the reactive and adsorbent materials were conducted with chemically designed evaluation system to measure the CO2 capturing efficiency.
Regulation of Double Perovskite Materials through a Structural Modification and Doping for an Effective Electrocatalyst in Water Electrolysis
Authors: Han Kyeongwon , Kim Heesu , Kim Hyungjin , Park Hyeonji , Song Jeongeun , Kim Boyean , Jeon Yukwon
Published: December 2024

Numerous electrochemical catalysts have been manufactured through various combiantions since the past, and they have been used in various fields. Among them, perovskite-based electrochemcial catalysts have high durability and electrochemical properties since they are composed of inorganic oxides. In addition, the electrochemical perovskite catalyst based on the transition metals shows comparable performance with high economic feasibility compared to the precious metal-based catalysts. In this study, double perovskite with a structure of A2BB’O6 containing the existing transition metal in the b-site are utilized to carefully modify the electrochemical properties. In order to utilize tungsten that has excellent electrochemical property, double perovskite structure was used because it is difficult to dope tungsten in a general single perovskite with stable structure. Tungsten is normally equilibrium in the metallic phase, but the oxidation state changes from 4+ to 6+ in the oxide phase when electrons start to move rapidly, consequently boosting the electrochemical property. Therefore, we designed and synthesized a tungsten-based double perovskite catalyst by a solid-state method with calcium(Ca) doped into the b-site to stabilize the perovskite structure. An exsolution method is also applied to form a myriad of metals on the catalyst surface by breaking the meta-oxide bond in the perovskite structure. These metal nanoparticles formed on the surface can promote the activity of the electro chemical catalysts with improved electrochemical properties in oxygen evolution reaction (OER) mechanism. To analyze the physical and chemical characteristics, X-ray diffraction (XRD) with Rietveld refinement and X-ray photoelectron spectroscopy (XPS) measurements are carried out. Rotating disk electrode (RDE) system is utilized to confirm the electrochemical performance of the prepared samples. Through cyclic voltammetry (CV) and linear sweep voltammetry (LSV) measurements, oxygen involved reactions are performed to prove the possibility on the W-based double perovskite materials as an oxygen electrocatalyst for water electrolysis with low-price.