bluuebunny/crossref_metadata_2025_split huggingface dataset:
Control of Hydrogen Concentration in Ingazno Thin Film Using Cryopumping System
Authors: Jung Seyeon , Sung Taehoon , Lee Sein , Kwon J.-Y. 
Published: July 2022

Recently, amorphous metal-oxide semiconductors (AOSs) such as indium gallium zinc oxide (IGZO) have attracted great attention with their lower power consumption and higher mobility than amorphous silicon in the display field. However, the threshold voltage (Vth) shift of IGZO thin film transistor (TFT) caused by their poor reliability leads to the drop panel luminance. Therefore, improvement of IGZO TFT reliability is necessary, which is largely influenced by oxygen vacancy and hydrogen. In particular, hydrogen has shown different roles inside the IGZO active layer by hydrogen concentration. At lower concentration, the hydrogen passivation of oxygen deficiency region induces the improvement of initial electrical characteristics and reliability [2]. Meanwhile, Vth shift and degradation reliability are generated at higher concentration owing to the hydrogen related defect states [3]. Therefore, controlling excess hydrogen is necessary for reliability enhancement.
In this work, IGZO thin film was fabricated by cryopumping system instead of a turbo molecular pump (TMP) for radio frequency sputtering to reduce hydrogen concentration. Cryopump is an adsorption type that enables excellent evacuation ability of hydrogen and moisture taking up most of the partial pressure in high vacuum. As a result, deposition of IGZO thin film with lower hydrogen impurity is available. The hydrogen concentration in the IGZO thin film using both cryopump and TMP was quantitatively analyzed by elastic recoil detection (ERD) analysis. Then, electrical characteristics of the self-aligned top-gate structure TFTs fabricated by both pumps were measured with bias stress conditions.
To sum up, we showed the improved reliability of IGZO TFT by controlling excess hydrogen using cryopumping system.

Fig.1. (a) Schematic of RF magnetron sputtering process with cryopump. (b) TOF-SIMS depth profiles of hydrogen concentration in IGZO film using TMP and cryopump

Acknowledgment

This work was supported by the Korea Evaluation Institute of Industrial Technology(KEIT) grant funded by the Korea government (MOTIE) (No. 2021-11-1283)

References

Chung, Ui-Jin, et al. "15‐1: Invited Paper: Manufacturing Technology of LTPO TFT." SID Symposium Digest of Technical Papers. Vol. 51. No. 1. 2020.

Hanyu, Yuichiro, et al. "Hydrogen passivation of electron trap in amorphous In-Ga-Zn-O thin-film transistors." Applied Physics Letters 103.20 (2013): 202114.

Mativenga, Mallory, et al. "Origin of light instability in amorphous IGZO thin-film transistors and its
suppression." Scientific reports 11.1 (2021): 1-12

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(Invited) Continuum Mathematical Modeling of Water Electrolysis: A Tutorial
Authors: Dizon Arthur , Liu Jiangjin , Weber Adam Z. 
Published: July 2022

Widespread use of hydrogen energy is contingent on the development of reliable and economical sources of hydrogen. Electrolysis from renewably-derived low-carbon electricity is a potentially viable method of hydrogen generation. Prime among the electrolysis technologies are those utilizing ion-conducting polymers (ionomers) including proton-exchange-membrane water electrolyzer (PEMWE). However, these technologies need to exhibit increased efficiency, performance, and durability to become commercially viable. Like most electrochemical devices, PEMWEs involve multiple components (e.g., catalyst, ionomer, transport layers, membrane, plates) and multiple phases, with phenomena occurring across different time and length scales. Furthermore, it is difficult to experimentally probe many of the species and phenomena during operation. Thus, mathematical modeling at the continuum level has been an invaluable aid in exploring, understanding, and optimizing PEMWE cell and components. This is especially true in the highly coupled and complex physics and chemistries that occur with the membrane-electrode assembly (MEA). The physics in a typical volume-averaged non-isothermal model include multiphase transport in porous media, concentrated-solution theory, Ohm’s Law, and Butler-Volmer kinetics, and ion, gas, and water transport in the ionomer.
In this talk, different modeling approaches, governing equations, and constitutive relationships will be described, including the benefits and limits of modeling. While focus will be on continuum equations and macroscale effects, detailed submodels and approaches for scaling to full cells and specific components, respectively, will be introduced. For example, as shown in Figure 1, one can perform an applied voltage breakdown and describe the different mechanisms resulting in the necessary applied overpotentials, which is useful in identifying opportunities for improving cell performance by quantifying the potential losses associated with a specific mechanism. In the talk, the generation of such analysis will be discussed including various approaches. Also shown in Figure 1 is how modeling can be used to elucidate safety concerns and identify issues to be resolved, in this case, nonlinear hydrogen crossover. Finally, future directions for multiscale modeling and multi-model coupling will be discussed.

Figure 1
Catalytically-Active Phases and Reaction Mechanism of Ni-Based and Co-Based Layered Double Hydroxides for the Oxygen Evolution Reaction
Authors: Zeng Zhenhua , Zhu Jing , Dionigi Fabio , Li Wei-Xue , Strasser Peter , Greeley Jeffrey 
Published: July 2022

Electrochemical water splitting using renewable energy is a key route to generate green H2 fuel. In this process, however, O2 generation at the anode through the oxygen evolution reaction (OER) is inherently slower by over four orders of magnitude than H2 generation at the cathode. Thus, improving OER efficiency has been a majority effort in electrolysis. Ni-based and Co-based layered double hydroxides (LDHs) are among the most active and studied catalysts for the oxygen evolution reaction (OER) in alkaline electrolytes. Because it happens under extremely oxidative aqueous conditions, however, in-situ crystal structures of the OER active phase are still largely unknown, significantly hindering the establishment of structure-property relationships.
In this talk, we provide the first direct atomic-scale evidence that, under applied anodic potentials, NiFe and CoFe LDHs oxidize from as-prepared α-phases to activated γ-phases. The OER-active γ-phases are characterized by about 8% contraction of the lattice spacing and switching of the intercalated ions from carbonate to potassium. The calculated surface phase diagrams indicate that surface O sites are saturated with H by forming bridge OH, and coordinatively unsaturated metal sites are poisoned by OH adsorption under OER conditions. These structures, and the associated reaction free energies, suggest that the OER proceeds via a Mars van Krevelen mechanism, starting with the oxidation of bridge OH at the reaction centers with dual metal sites, i.e., M1-OH-M2.
Our study suggests that the compound-dependent activity originates from the dual-metal site feature of the reaction centers. While this feature does not influence the OH-OOH scaling relationship, it leads to diverse OH-O scaling relationships, including those with near-zero slopes and negative slopes. Breaking OH-OOH scaling relationships were frequently discussed in the literature, as it determines the minimum overpotential. However, our study showed that, to approach the minimum overpotential dictated by a specific OH-OOH scaling relationship, the key is to break the OH-O scaling relationship. A possible route is to form binary metal oxyhydroxides with dual metal sites at the reaction centers or introduce a third element into NiFe LDH or CoFe LDH.
References:
Dionigi, Z. Zeng, I. Sinev, T. Merzdorf, S. Deshpande, M. B. Lopez, S. Kunze, I. Zegkinoglou, H. Sarodnik, D. Fan, A. Bergmann, J. Drnec, J. F. d. Araujo, M. Gliech, D. Teschner, J. Zhu, W.-X. Li, J. Greeley, B. R. Cuenya, P. Strasser, Nature Communications
2020, 11, 2522.
Dionigi, J. Zhu, Z. Zeng, T. Merzdorf, H. Sarodnik, M. Gliech, L. Pan, W.-X. Li, J. Greeley, P. Strasser, Angew. Chem., Int. Ed.
2021, 60, 14446-14457.
(Digital Presentation) Synergistic Effect of Cobalt and Nitrogen on the Spent Coffee Grounds Derived Carbon As an Efficient Catalyst for Alkaline Hydrogen Evolution
Authors: Sukhbaatar Bayaraa , Yoon Sanghwa , Yoo Bongyoung 
Published: July 2022

Due to global electricity demand and ecological issues, eco-friendly and sustainable energy resource is becoming a hot topic in energy production and future economic development. On this point, efficient catalytic materials for electrochemical hydrogen evolution reaction (HER) are crucial in the research area. HER in alkaline medium has several advantages, including its lower vapor pressure, which helps produce pure hydrogen gas and provides better stability than acidic medium to metal contents by reducing catalyst’s corrosion. Primarily, carbon-based electrocatalytic materials such as hetero-atomic-doped carbon, transition metal-doped carbon, and co-doped carbon show off an effective HER performance. Because it has a large surface area, good chemical stability, it is inexpensive and earth-abundant.
Additionally, spent coffee grounds (SCG) contain a high amount of carbohydrates, melanoidins, and lipids that are given a possibility to be suitable carbon precursors for carbon catalyst synthesis. Moreover, SCG is becoming an environmental issue that produces many tons of waste worldwide each year due to the proliferation of global coffee consumption.
Here, we present cobalt nanoparticles embedded on nitrogen (N)-doped carbon catalyst, synthesized from SCG. Initially, SCG-derived nanoporous carbon was obtained by pyrolysis under high temperatures with KOH and urea. After that, carbon materials were functionalized with cobalt and nitrogen with the simple method.
Cobalt-embedded N-doped carbon catalyst has a high surface area and highly distributed nano-sized pores. Polarization measurement, Tafel plot, electrochemical impedance spectroscopy, chronopotentiometry, and cyclovoltammetry have tested the electrochemical performance. Even though the catalyst contained a negligible amount of cobalt (0.56 at. %), HER catalytic activity in alkaline medium has better resulted than non-functionalized carbon catalysts and was comparable to higher activity benchmark electrocatalysts such as RuO2 and 20% Pt/C. Also, experimental results demonstrate that excellent long-term stability for the alkaline hydrogen evolution. So, synergistic effects of cobalt nanoparticles content and N-doping on the SCG-derived carbon were indicated for efficient catalyst in the alkaline hydrogen evolution application.
High-Performance Fiber-Shaped Zn Microbattery Based on Dendrite-Free Anode and Ultraconductive Cathode
Authors: Zhai Shengli , Li Zhi 
Published: July 2022

Rechargeable Zn-ion microbatteries emerge as a promising power solution due to their remarkable safety, high capacity, low cost, simple manufacturing, and environmental friendliness. Their fiber-shaped counterparts are particularly attractive due to their lightweight, tiny volume, and mechanical flexibility. However, it is still fundamentally challenging to construct high-performance fiber-shaped Zn-ion microbatteries (FZMB) because of the dendrite growth at the anode, the poor electrical conductivity of current cathode materials, the lack of suitable fiber substrates (high electrical conductivity and strong interaction with cathode materials).
We developed a simple and scalable process to fabricate dendrite-free fiber anodes by sputtering an ultrathin conductive carbon layer on rock-like Zn deposits around carbon fibers (CF) . The carbon layer plays a critical role in suppressing dendrites by uniformizing the surface electric field and provide additional surface and abundant nucleation sites. The obtained CF@Zn@C can stably run over 200h. Plus, we demonstrate a highly conductive and well-interacted fiber cathode, i.e., PEDOT: PSS@PANI core-sheath fiber, with a record high conductivity of 3676 S cm−1. The superior conductivity enables a fast electron transfer which is beneficial to high rate performance. Based on the same PEDOT: PSS platform, we have fabricated the next-generation FZMB by using citriate as electrolyte additives to suppress the dendrite formation. Compared to the carbon layer on the Zn anode, the use of additives in the electrolyte is much easier in production. .

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(Invited) Sustainability, Safety, Scalability, Rechargeability, and Manufacturability Courtesy of Architected Zinc Anodes
Authors: DeBlock Ryan H. , Hopkins Brandon J. , Ko Jesse S. , Parker Joseph F. , Chervin Christopher N. , Skeele Nathaniel L. , Long Jeffrey W. , Rolison Debra R. 
Published: July 2022

Towards the goal of decarbonizing electrification, concerns remain over the sustainability of the requisite Li and Co, as well as the stringent transportation limits on the amount and operational state of Li allowed in airfreight. Rechargeable zinc-based batteries using aqueous electrolyte offer a compelling alternative to lithium-based batteries with the added benefit of a two-electron anode that augments the energy density, helping to compensate for lower cell voltage inherent to aqueous electrolytes. To solve the standing caveat with rechargeable zinc-based batteries — that they form separator-piercing dendrites — we built on our understanding of the importance of 3D co-continuous wiring of electrons, ion, and molecules in energy-storing nanoarchitectures. Sponge form factors fabricated by fusing ~50 µm zinc particles into a monolithic pore–solid architecture physically prevents formation of dendrites even at high charging current density [1,2]. Throughout the story of the NRL Zn sponge anode, each successive generation of the electrode has been fabricated with manufacturability as a foremost consideration, such that the current sponge formulation (Gen 5) is processed quickly, at scale, to sizes necessary for decarbonizing electrification. I will present the performance of these “big and strong” zinc sponges versus a variety of cathodes and the potential paths forward for the development and transition of this safer energy-storage technology.
[1] J.F. Parker, C.N. Chervin, E.S. Nelson, D.R. Rolison, J.W. Long, “Wiring zinc in three dimensions re-writes battery performance―Dendrite-free cycling.” Energy Environ. Sci., 7, 1117–1124 (2014).
[2] J.F. Parker, C.N. Chervin, I.R. Pala, M. Machler, M.F. Burz, J.W. Long, and D.R. Rolison, “Rechargeable nickel–3D zinc batteries: An energy-dense, safer alternative to lithium-ion.” Science, 356, 415–418 (2017).
Effect of Tungsten Oxide Structure on Enhancing the V(II)/(VIII) Reaction and Inhibiting H2 Evolution for All-Vanadium Redox Flow Battery
Authors: Al Najjar Taher , K. Allam Nageh , El Sawy Ehab 
Published: July 2022

Renewable energy sources require high-efficiency storage systems to allow for its integration within the electrical grid and to supply that energy when needed. All-vanadium redox flow batteries (VRFBs) are very promising for this application because they can store high amounts of energy, are designed to work for long periods, and their solutions can be used indefinitely.1 VRFBs have various advantages when combined with renewable energy sources. The relatively high cost of VRFBs limits their widespread deployment. Enhancing the kinetics of the electrochemical reactions is needed to increase the power density and energy efficiency of the VRFB, and hence decrease the kWh cost of VRFBs. Different carbon materials are used as electrodes in VRFBs (carbon felt, paper and cloth), and each of these materials affects the performance of the battery differently either through sluggish kinetics or a high chance for parasitic reactions catalyzation.2 Modification of these electrodes by carbon-based3 or metal oxides2 nanomaterials can increase the power density of the battery and suppress the parasitic reactions. Some metal oxides like tungsten oxide4 can enhance vanadium reactions alone or when used as composites with nanocarbon materials.
This work aims at enhancing the VRFBs negative half-cell reaction (V2+/V3+) kinetics and inhibiting the hydrogen evolution parasitic reaction. Carbon cloth electrodes were modified, using different tungsten oxide nanostructures such as nanowires, nanoflakes, and nanospheres, and tested at different loadings. The results suggest that the change in tungsten oxide structure would lead to a change in the electrode overall performance as a result of changing the electrical conductivity, the wettability of the electrodes, the coverage of the carbon cloth, and the number and nature of the active sites available to catalyze the V2+/V3+ reaction, with the tungsten oxide nanowires showing to be the best electrode modifier.

References:

R. K. Sankaralingam, S. Seshadri, J. Sunarso, A. I. Bhatt, and A. Kapoor, Journal of Energy Storage, 41, 102857 (2021).

A. Wodaje Bayeh et al., Sustainable Energy & Fuels, 5, 1668–1707 (2021).

F. A. E. Diwany, B. A. Ali, E. N. E. Sawy, and N. K. Allam, Chem. Commun., 56, 7569–7572 (2020).

M. Faraji, R. Khalilzadeh Soltanahmadi, S. Seyfi, B. Mostafavi Bavani, and H. Mohammadzadeh Aydisheh, J Solid State Electrochem, 24, 2315–2324 (2020).
High-Capacity Bio-Inspired Redox Flow Batteries with Insoluble Redox Boosters
Authors: Gokoglan Barut Tugba Ceren , Pahari Shyam Kumar , Visayas Benjoe Rey B. , Aravamuthan Sundar Rajan , Mayes Maricris L. , Cappillino Patrick J. , Agar Ertan 
Published: July 2022

Redox flow batteries (RFBs) are considered to be one of the key technologies for addressing the intermittency problem in renewable energy sources, due to their unique architecture that allows for unprecedented scalability and flexibility, and cost-effectiveness in long-duration storage [1]. Despite their promise, typical RFBs suffer from low energy density because of the limit imposed by the solubility of the redox active species in the electrolyte [2]. One promising approach to bypass the solubility limitation and drastically improve the energy density is the addition of insoluble charge storage materials into the electrolyte tanks. These redox active materials are reversibly oxidized/reduced in the tanks upon interaction with the redox active species dissolved in the electrolyte. Thus, the capacity is no longer dependent on the concentration of soluble species but rather the quantity of solids in the tanks [3-4]. This new concept is called redox-mediated flow battery (RMFB).
In this presentation, we demonstrate a high energy density RMFB using a highly stable bio-inspired active material (vanadium(IV/V)bis-hydroxyiminodiacetate (VBH)) and a suitable solid storage material. VBH, as a high-stability active material [5], provides an ideal scaffold to investigate the complex electrochemical processes that occur during RMFB operation, which remain virtually unexplored [6]. For the solid storage material, a Prussian Blue Analogue (PBA) is synthesized and coupled with VBH mediators. Symmetric cell cycling experiments are performed with and without the solid energy booster material to provide evidence that the addition of a compatible solid material greatly improves the energy density. Compatibility between the PBA and VBH is investigated using cyclic voltammetry (CV) experiments. Optimization of the critical parameters such as the amount of solid storage material, the operating current density, and the electrolyte flow rate is presented.

References:

[1] Z. Li, M. S. Pan, L. Su, P.-C. Tsai, A. F. Badel, J. M. Valle, S. L. Eiler, K. Xiang, F. R. Brushett, Y.-M. Chiang, Joule, 1, 306-327 (2017).
[2] S. K. Pahari, T. C. Gokoglan, B. R. B. Visayas, J. Woehl, J. A. Golen, R. Howland, M. L. Mayes, E. Agar, P. J. Cappillino, RSC Adv., 11, 5432-5443 (2021).
[3] R. Yan, Q. Wang, Adv. Mater., 30, 1802406 (2018)
[4] X. Wang, M. Zhou, F. Zhang, H. Zhang, Q. Wang, Curr. Opin. Electrochem.,
29, 100743 (2021).
[5] T. C. Gokoglan, S. K. Pahari, A. Hamel, R. Howland, P. J. Cappillino, E. Agar, J. Electrochem. Soc.,
166, A1745-A1751 (2019).
[6] M. Moghaddam, S. Sepp, C. Wiberg, A. Bertei, A. Rucci. P. Peljo, Molecules, 26, 2111 (2021).
A Molten-Salt Battery for Seasonal Energy Storage
Authors: Li Minyuan Miller , Weller Jon Mark , Polikarpov Eugenia , Reed David , Sprenkle Vincent , Li Guosheng 
Published: July 2022

Cost-competitive renewable energy sources, such as wind and solar energy, are more rapidly replacing fossil fuels for power generation. As their integration into the power grid increases, the inherent intermittency exposes a great challenge in maintaining the grid stability. Therefore, the development of low-cost energy storage technology suitable for large-scale manufacturing is essential for the further deployment of renewable energy. We noticed that renewable electricity production usually follows predictable seasonal trends. For example, the longer daylight in summers corresponds to more solar power generated. If any seasonal excess can be efficiently stored and redistributed in times of needs, a power grid based on 100% renewable energy is more feasible. Unfortunately, current rechargeable battery technologies have not been optimized for seasonal storage, as the self-discharge rate ranges from approximately 3–5% for lithium-ion batteries to almost 30% for nickel metal hydride batteries in the first month.
In this presentation, we will demonstrate the concept of a rechargeable molten-salt battery with earth-abundant elements and simple construction that preserve the stored energy for long periods of time. Due to its unique operating mechanism, this battery can discharge most of its stored capacity (> 90%) after a period of 1 to 8 weeks. This approach brings new possibilities to seasonal energy storage and helps the grid to overcome short supply during seasonal fluctuations.