bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analyzing the Doping Mechanism of High-Valence Element in Ni-Rich Cathode Materials
Authors: Kim Myoung-Chan , Park Nam-Yung , Sun Yang-Kook 
Published: August 2024

Layered cathode materials, LiMO2 (M=Ni, Co,Mn, or Al), with a high nickel content are promising cathode materials owing to their near-theoretical specific capacity. However, the inherent chemical and structural instabilities of Ni-rich cathodes lead to several problems, including rapid capacity fading, thermal instability, gas evolution, and safety concerns.1

Introducing additional elements into Ni-rich cathodes is an essential strategy for addressing the instability of the cathode material. Conventionally, this doping strategy considers only the incorporation of additional elements into the bulk structure of the cathode in terms of fortifying the crystal structure.2 However, high-valence elements are likely to be insoluble in the crystal structure, resulting in accumulation along the interparticle boundaries.3 Herein, a new mechanism for doping high-valence elements into Ni-rich cathodes and their effects on the morphology and crystal structure are investigated by calcining LiNiO2 (LNO) and X-doped LNO cathodes (X=Al, Nb, Ta, and Mo) at various temperatures. Operando X-ray diffraction analysis reveals that the temperature at which the content of Li-X-O compounds declines is higher for the dopants with high oxidation states, reinforcing segregation at the grain boundary. Thus, the highly aligned microstructure and high crystallinity of the LNO cathode are maintained over a wide calcination temperature range after doping with high-valence elements, enhancing the electrochemical performance.

References:

[1] N.-Y. Park, G.-T. Park, S.-B. Kim, W. Jung, B.-C. Park, Y.-K. Sun, ACS Energy Lett.
2022,7, 2362.
[2] X. Ou, T. Liu, W. Zhong, X. Fan, X. Guo, X. Huang, L. Cao, J. Hu, B. Zhang, Y. S. Chu, G. Hu, Z. Lin, M. Dahbi, J. Alami, K. Amine, C. Yang, J. Lu, Nat. Commun.
2022,13, 2319.
[3] G.-T. Park, D. R. Yoon, U.-H. Kim, B. Namkoong, J. Lee, M. M. Wang, A. C. Lee, X. W. Gu, W. C. Chueh, C. S. Yoon, Y.-K. Sun, Energy Environ.Sci.
2021,14, 6616.
Influences on Reliable Capacity Measurements of Hard Carbon in Highly Loaded Electrodes
Authors: Müller Cedric , Wang Zhengqi , Hofmann Andreas , Stüble Pirmin , Liu-Théato Xinyang , Klemens Julian , Smith Anna 
Published: August 2024

Lithium-ion batteries (LIBs) are the current state of the art energy storage technology. However, to tackle the steady increasing demand for clean but also sustainable energy, other complementary cell chemistries are gaining significant importance. Sodium-ion batteries (NIBs) are considered to be a drop-in technology that can benefit from the knowledge about processing of LIBs and its existing manufacturing structures.
For the development of a sodium-ion full-cell, commercially available hard carbon (HC) as an anode material was characterized within a half-cell setup. On the one hand, those measurements are essential to characterize individual electrodes in order to obtain electrochemical information that is needed to set up the full cell, e.g. balancing. On the other hand, the exact determination of the HC capacity is prone to errors, mainly due to the cut-off potential being close to 0 V against metallic sodium. This behavior and also electrolyte degradation in presence of elemental sodium were studied.
It has been found that the potential of the current carrying sodium counter electrode in half-cells is not stable, resulting in measurement inaccuracies, particularly at elevated C-rates when charging is controlled by a cut-off potential. On the contrary, by using a three-electrode setup, the current-free reference electrode provides stable cut-off conditions. An improved setup for half-cell measurements is suggested to obtain reliable and reproducible capacity readings for HC anodes with an areal capacity of up to 2.4 mAh/cm².

Figure
: Schematic overview about the investigated control voltages and their effect on the electrochemical performance.
[1]

The initial coulombic efficiency (ICE) of HC is a current challenge because it is relatively low at about 80% and it can vary for different HC materials. Therefore, precise measurements are a necessity to develop HC materials with higher ICEs.
Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2154.
[1] Müller, C., Wang, Z., Hofmann, A., Stüble, P., Liu-Théato, X., Klemens, J., Smith, A., “Influences on Reliable Capacity Measurements of Hard Carbon in Highly Loaded Electrodes” Batteries & Supercaps 2023, e202300322.

Figure 1
Measurement of Li-Ion Self-Diffusion in Laser Structured Electrodes
Authors: Tambio Sacris Jeru , Deschamps Michael , Pfleging Wilhelm 
Published: August 2024

It is generally stated that a limiting factor in fast charging and high-power discharging of lithium-ion batteries (LiB) stems from the diffusion kinetics of Li+ in the electrode pore network. Numerous approaches in enabling fast charging of LiBs include active material development, electrolytes with high ionic conductivity and the management of the charging and discharging temperature. Another promising method is laser micro structuring to modify the electrode architecture regarding an enhanced lithium-ion diffusion kinetics. An increased high-rate capability and boost in cell lifetime have been demonstrated with such 3D electrodes [1, 2] but the related mechanisms leading to a substantial impact to diffusion kinetics are still poorly understood. Furthermore, it is imperative to find an optimal ablation pattern with regard to the desired application scenario that minimizes active mass loss in order to create the economic basis for efficient upscaling of the process.
Nuclear Magnetic Resonance (NMR) measurements of longitudinal (T1) and transverse relaxation times (T2), as well as the T2/T2 exchange, are routinely used for the identification of different molecular species. The exchange NMR experiment is a well-known technique for studying local environments of nuclei such as liquids in pores and approximating their shapes and sizes [3]. The evolution of the transverse relaxation rate (T2) of a probed nuclei allows to determine if the specie is confined (shorter T2) or in liquid bulk (longer T2). In this work, so-called Exchange Nuclear Magnetic Resonance (T2/T2 exchange or EXSY), is conceptualized to study the impact of laser generated 3D patterns in pore self-diffusion of electrolyte species.
Exchange NMR and T1 and T2 measurements were realized at various soaking times and electrolyte amounts for the following electrolyte species: Li+, PF6
-, ethyl carbonate (EC), and ethyl methyl carbonate (EMC), using laser structured, graphite-based electrodes casted on non-metallic substrates (to reduce RF interference). 2D exchange maps show the presence of confined species as well as the approximation of the diffusion properties. Using isotope exchange experiments with 6Li enriched electrolyte, concentration maps revealed the rate of 6LiPF6 intrusion into 7LiPF6 rich pre-soaked electrodes. The impact of laser generated 3D patterns in pore diffusion will be discussed in detail.
[1]. Zheng, Y. et al. 3D silicon/graphite composite electrodes for high-energy lithium-ion batteries. Electrochim. Acta
317, 502–508 (2019).
[2]. Smyrek, P., Pröll, J., Rakebrandt, J.-H., Seifert, H. J. & Pfleging, W. Manufacturing of advanced Li(NiMnCo)O2 electrodes for lithium-ion batteries . Laser-based Micro- Nanoprocessing IX
9351, 93511D (2015).
[3]. Mitchell, J. et al. Validation of NMR relaxation exchange time measurements in porous media. J. Chem. Phys.
127, (2007).
A Low-Cost Iron-Based Substrate for Alkaline Battery Electrodes
Authors: Maniyanganam Ahamed Irshad , Mitra Debanjan , Rajan A Sundar , Trinh P , Balasubramanian Mahalingam , Tomar Yeshvi , Prakash G. K. Surya G. K. , Narayan Sri 
Published: August 2024

The nickel foam current collector adds significantly to the cost of the positive electrode of nickel-based alkaline batteries.1 Iron is roughly 40 times less expensive than nickel; but iron corrodes at the operating potential of the nickel electrode at pH 14 or higher.2 Thus, for an iron substrate to be viable, it should be protected from anodic corrosion in alkali and the surface must be electrically conducting. We found that a 100 nm thick thermal coating of cobalt ferrite protects iron from corrosion. The protected iron substrate was stable for 1000 h even when anodically polarized at 10 mA cm−2 in 30% potassium hydroxide battery electrolyte.3 The electrical conductivity of the coating could be improved by the incorporation of lithium-ions. The enhanced conductivity was attributed to an increase in the population of Co3+ in the spinel lattice as evidenced from XPS and XAS analyses.4 The nickel electrode on such an inexpensive iron-based substrate exhibited a specific capacity of 0.25 Ah g−1 at C/5 discharge rate, comparable to a nickel hydroxide electrode on expensive nickel foam. The electrode also exhibited no noticeable degradation for 150 cycles at C/2 rate. This robust and economical iron substrate thus presents a unique opportunity for reducing the cost of the nickel electrode in aqueous alkaline batteries.
References:
(1). J. Chen, D. H. Bradhurst, S. X. Dou, and H. K. Liu, J. Electrochem. Soc., 146, 3606 (1999)
(2). B. Beverskog and I. Puigdomenech, Corros. Sci., 38, 212 (1996)
(3). A. Irshad, D. Mitra, A. Sundar Rajan, P. Trinh, M. Balasubramanian, and S. R. Narayanan, J. Electrochem, Soc,, 167, 020543 (2020)
(4). V. Pralong, A. D. Vidal, B. Beaudoin, J. B. Leriche, and J. M. Tarascon, J. Electrochem. Soc., 147, 1306 (2000)

Figure 1
Regulating Sn Metal Growth Towards Highly Reversible Anode in Aqueous Acidic Batteries
Authors: Zhang Haozhe , Lu Xihong , Meng Shirley 
Published: August 2024

Safe and cost-effective aqueous acidic batteries (AABs) offer substantial promise for renewable energy storage, as it have the potential to achieve greater energy and power density by utilizing non-metal hydrate protons as charge carriers.1 However, most of traditional aqueous anode electrodes (Zn, Fe, etc.) have incompatibility with AABs due to the instability in acid, resulting in the quite limited choice of anode materials in acidic environment.
In prior research, we successfully demonstrated that Sn metal can serve as a highly suitable anode material for AABs.2 This is attributed to its comparatively high overpotential for the hydrogen evolution reaction (HER), substantial theoretical capacity (451.6 mAh g−1), and negative redox potential (−0.14 V vs. SHE).3 The critical issue is that Sn tends to form polyhedral particles during the electro-deposition due to the small difference in surface energy between different planes.4 Along with the increase of capacity, the polyhedron Sn particles may become detach and fragment, ultimately leading to the formation of inactive, or dead Sn, which significantly impacts the cycling stability of Sn anode and even cause severe HER.
We will present our efforts of developing reversible Sn anode for AABs by regulating Sn metal growth. Our first work applies interfacial alloying regulation to achieve smaller grain size and more uniform Sn deposition by higher propensity for nucleation and Sn migration energy barrier, thus increased the anode reversibility. The following work successfully selected a HER-inert crystal plane and achieved its preferential growth used cationic surfactants electrolyte additive. A dense and compact Sn film is obtained by adjusting the adsorbed species on the Sn surface, and no dead Sn was observed after cycling. Based on these regulated Sn metal anodes, we demonstrated several Sn-based AABs (MnO2//Sn, PbO2//Sn, etc.), with promising performance on output voltages, specific energy densities, kinetics, and lifespans.

References

X. Wu, J. J. Hong, W. Shin, L. Ma, T. Liu, X. Bi, Y. Yuan, Y. Qi, T. W. Surta, W. Huang, J. Neuefeind, T. Wu, P. A. Greaney, J. Lu, X. Ji. Nat. Energy
2019, 4, 123-130.

H. Zhang, D. Xu, F. Yang, J. Xie, Q. Liu, D. Liu, M. Zhang, X. Lu, Y. S. Meng. Joule
2023, 7, 971-985.

W. Zhou, S. Ding, D. Zhao, D. Chao. Joule
2023, 7, 1099-1110.

Y. Yao, Z. Wang, Z. Li, and Y. Lu. Adv. Mater.
2021, 33, 2008095.
(Invited) C60-Based Switchable Fluorescent Probes
Authors: Ma Yue , Persi Lorenzo , Yan Shen , Baumgartner Martin , Yamakoshi Yoko 
Published: August 2024

Photodynamic therapy (PDT), an emerging non-invasive tumor treatment, requires suitable photosensitizer (PS) molecules that generate reactive oxygen species (ROSs) efficiently under long wavelength of light with deep tissue penetration, ideally activated in the diseased tissue. C60 is known as an excellent acceptor molecule in both electron- and energy-transfer reactions and exhibits biocompatibility and efficient ROS generation, rendering it a promising candidate as a PS for PDT.
In this study, we developed a C60-based dual-functional molecular probe containing a water-soluble C60-peptide and a donor fluorophore connected with a ligand peptide specific for matrix metalloproteinases (MMP) (Figure 1). We expect that such a molecular probe can be used in both diagnostic imaging and concurrent treatment. The probe revealed increased fluorescence signal and 1O2 generation in the presence of MMP2/9 enzymes that are known to be overexpressed in tumor cells. Furthermore, in vitro cellular tests demonstrated the probe's abilities in imaging MMP activity and photocytotoxicity on MMP-expressing tumor cells.

Figure 1
(Invited) Reactivity on Endohedral Metallofullerenes
Authors: Abella Guzman Laura , Rodriguez-Fortea Antonio , Poblet Josep M. 
Published: August 2024

Endohedral metallofullerenes (EMFs) are fullerene molecules with unique host-guest structures that allow chemists to manipulate encapsulated metal ions with the arsenal of organic chemistry, for potential applications including spin-quantum computing, single-molecule magnets, dynamic nuclear polarization, artificial photosynthesis, magnetic resonance imaging contrast agents, and therapeutic agents. To unleash the power to do so, the development of new reactions for EMFs has been an ongoing task.
A key step to improve the solubility of EMFs as well as to obtain new materials for multiple applications is via exohedral functionalization. In medicine, for instance, water-soluble gadofullerenols are used as powerful contrast agents.1 Besides, the external groups might impart complementary features to EMFs that tune their physical properties for use as acceptors in polymer solar cells or as donor-acceptor dyad conjugates.2 Among the most used methods to obtain EMF monoadducts are cycloaddition reactions and radical additions, including the Diels-Alder cycloaddition, Bingel-Hirsch cyclopropanation, Prato 1,3-dipolar addition, carbene addition, etc. In these reactions, fullerenes typically play a similar electron-accepting role, thus their reactivity and regioselectivity are highly consistent. However, the reactivity of EMFs is far more complicated than of empty fullerenes due to the relatively low molecular symmetry and the influence of the encapsulated species. To understand the role of metal-cage interactions on the reactivity of EMFs is desirable for tuning their chemical reactivity.
Here, we report the functionalization of actinide endofullerenes, in particular, the mono-EMFs U@C
s(4)-C82 and U@C
2v(9)-C82, which their chemical reactivities were investigated through the Bingel-Hirsch (nucleophilic addition) and carbene addition (electrophilic addition) reactions. Interestingly, only for U@C
2v(9)-C82, the Bingel-Hirsch reaction leads to mono-adduct and multi-adduct compounds. Another subgroup of EMF that we study its reactivity here is the nitride clusterfullerenes, especially the Lu3N@Ih-C80, with high stability and high production yields, that results its chemical modification to be challenging. In this case, the reaction studied is the inverse-electron demand Diels-Alder (IEDDA) reaction and it will be compared to the corresponding reactivity on C60 fullerene. We show that Lu3N@Ih-C80presents higher reactivity than for C60, as well as, different features.

1Bolskar, R. D.; Benedetto, A. F.; Wilson, L. J.; Alford, J. M. et al. J. Am. Chem. Soc. 2003, 125, 5471-5478.

2Ross, R. B.; Cardona, C. M.; Guldi, D. M. et al. Nature Mater. 2009, 8, 208-212.

Figure 1
Invited: Mimicking Biological Synapse Activity with LDH-Based Memristor
Authors: Ignatova Tetyana 
Published: August 2024

Memristors, mimicking biological synapse response, are believed to have a great potential for use as an adaptive memory unit in future neuromorphic computing systems. Here we report on fabrication of two-dimensional memristor comprised of layered double hydroxide (LDH) material, covered with graphene layer, serving as a terminal for connecting to electrodes. We demonstrated nonvolatile resistive switching of LDH memristor. Device performance is studied upon replacing graphene semimetal with alternative 2D materials. Comprehensive characterization of the memristor materials was performed with correlated Raman, Electron, and Scanning Probe Microscopy methods.
ACKNOWLEDGMENT
This work was supported by the US Department of Defense (Contract #W911QY2220006), 2DCC-MIP NSF cooperative agreement DMR-2039351. Work was performed at JSNN, a member of the Southeastern Nanotechnology Infrastructure Corridor (SENIC) and National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the NSF (ECCS-1542174)
(Nanocarbons Division Poster Award, 3rd Place) Hybrid Supercapacitance and Stability of Fe-Based Metal-Organic Frameworks/Graphene Oxide Nanoribbons Composite Allover the pH Range
Authors: Heiba Asmaa R. , Abdelsalam Mohamed O , Yoon Taeho , El Sawy Ehab N 
Published: August 2024

Adopting renewable energy sources is growing fast, and hence it should be accompanied by tremendous efforts to develop energy storage technologies that can mitigate the intermittent nature of these sources. Supercapacitors (SCs) are considered among the most promising technologies for that purpose due to their high durability, power density, and charging/discharging competency. SCs have two types according to their electrochemical charge storage mechanism: pseudocapacitance (PCs) or battery-like behavior and electrochemical double-layer capacitors (EDLCs). The development of next-generation supercapacitors requires a holistic approach that integrates both mechanisms. Because of their huge surface area, porous structure, and abundance of active redox sites, metal-organic frameworks (MOFs) have exceptional potential in energy storage devices. However, due to the MOFs’ low conductivity and stability, they are in need to be mixed with highly conductive and stable materials such as carbon-based ones.
In this work, Fe-based MOFs were selected to be responsible for mainly the battery-like contribution to the overall supercapacitance due to the presence of the redox-active sites. Even though little attention has been given to the Fe-based MOFs they showed a promising performance in several solutions, with low stability.1,2 To enhance the Fe-MOFs stability and conductivity and add an EDLC component to the overall capacitance behavior graphene oxide nanoribbon (GONRs) was used. The GONRs' exceptional properties such as ultrathin two-dimensional structures, superior mechanical behavior, strong chemical stability, and high electrical conductivity make them promising materials for supercapacitor applications.
In this study, Fe-MOFs were synthesized using a hydrothermal method,3 and GONRs were prepared using an oxidative unzipping method.4 A composite of Fe-MOFs/GONRs was prepared by physical mixing. The physical and chemical properties of the synthesized Fe-MOFs, GONRs, and Fe-MOFs/GONRs were characterized using XRD, SEM, TEM, FT-IR, Raman spectroscopy, and XPS. Since the electrolyte properties have a substantial impact on the supercapacitive behavior and stability of the electrode materials, the specific capacitance of the prepared composites was measured in 1M H2SO4, 1M KOH, 1M K2SO4, and 1M KCl utilizing different evaluation systems (three and two-electrode systems). The Fe-MOFs/GONRs composite showed a significant synergistic effect in comparison to its pure components. Further discussion will be given regarding the pH and ion size/type effect on the supercapacitive performance and stability.

References:

B. Ramasubramanian et al., Surf. Interfaces, 34, 102397 (2022).

J. Xie, R. Ma, H. Fang, H. Shi, and D. Liu, Cryst. Growth Des., 22, 2997–3006 (2022).

J. Joseph et al., Chemosphere, 284, 131171 (2021).

D. V. Kosynkin et al., Nature, 458, 872–876 (2009).
A Rechargeable Solid-State Sodium-Oxygen Battery with Enhanced Energy Efficiency and Cycle Life
Authors: mosen Harzandi Ahmad , Azaribeni Adel , Asadi Mohammad 
Published: August 2024

Sodium-oxygen (Na-O2) batteries offer a promising path for the advancement of high-energy-density inexpensive storage systems to replace current state of the art Li-based batteries owing to the natural abundance and low-cost Na metal. Despite numerous studies to improve the performance of liquid-based electrolyte Na-O2 batteries, this technology suffers from poor cycle life, electrolyte stability issues, and limited choice of cell design as well as growing safety concerns associated with liquid electrolytes. Recently, solid electrolytes received a great attention to substitute traditional liquid electrolytes used in Na-O2 batteries, due to their ability of improving safety and energy density. However, low ionic conductivity and high impedance in contact with the anode and cathode remain as major challenges for the development suitable solid-state electrolyte for Na-O2 batteries.
In addressing these challenges, we recently have established a solid-state Na-O2 battery cell that comprises a highly conductive composite polymer-ceramic solid electrolyte with a conductivity of 0.7 mS/cm. This solid electrolyte works in synergy with vanadium phosphide (VP) nanoparticles, serving as oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalysts at the cathode and Na metal anode for more than 500 reversible charge-discharge cycles at a capacity of 1000 mAh/g, achieving a low polarization gap of approximately 20 mV in the first cycle. Various electrochemical and physicochemical characterization techniques, such as Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), differential electrochemical mass spectrometry (DEMS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were employed to gain insight into the cell chemistry and solid-state electrolyte role in the formation and decomposition of sodium oxides components such as superoxide (NaO2), peroxide (Na2O2). The findings of this study underscore the significance of proper cell component design and possible mechanisms in solid-state Na-O2 battery technologies. This research represents a promising avenue in advancing energy conversion and storage systems, showcasing the potential of solid-state batteries with enhanced safety and performance characteristics.