bluuebunny/crossref_metadata_2025_split huggingface dataset:
Centrifugal Jet-Spun, Non-Woven Chitin Fiber Separator for High-Performance Aqueous Zinc-Ion Batteries
Authors: Jin Jungho , Song Myeong-Oh , Park Jeong-Ho , Jung Ji-Won 
Published: August 2024

Although lithium-ion batteries (LIBs) are key prevailing energy storage devices, alternative battery technologies based on earth-abundant materials are being sought as a viable energy storage systems that could possibly replace LIBs. Among several alternatives is aqueous zinc-ion batteries (AZIBs), which are more eco-friendly, cost-effective, and even safer. Despite their potential advantages, the development of appropriate separators for ZIBs has been elusive, and the issue of zinc metal dendrites on the negative electrode remains a critical challenge.
In this work, we introduces a novel approach to prepare a non-woven spun fiber mat made of chitin, an abundant natural polymer, which could function as a separator for AZIBs. In particular, we use centrifugal jet-spinning (CJS) to fabricate the chitin separator. The use of chitin as a separator offers several advantages over existing ZIB separators, such as high stability, improved capacity, environmental friendliness, and cost-effectiveness. We demonstrate that the chitin separator can be applied in AZIB cells based on symmetric and full cell models, which showed stable cell operation for long-term cycling.

Figure 1
On-Surface Synthesis of 1D and 2D π-Conjugated Polymers from Heterotetrabromo-P-quinodimethanes (HTBQs)
Authors: Jimenez Vicent Diego , Pérez Elvira Elena , Santos Jose , Urgel Jose , Ecija David , Martín Nazario 
Published: August 2024

Molecules bearing gem-dibromoolefines functionalities have been employed in wet chemistry as intermediates in the well-known Corey-Fuchs homologation of carbonyls to alkynes. This gem-dibromoolefines can be embedded into tetrabromo-p-quinodimethanes (TBQs), which efficiently undergo dehalogenative homocoupling on coinage metal surfaces, namely Au(111) and Ag(111), forming one-dimensional (1D) acene and periacene π-conjugated polymers able to exhibit non-trivial topological properties.[1,2]
However, the synthesis of more complex π-conjugated polymers to determine the scope of this new reaction, as well as the synthesis of two-dimensional (2D) polymers by following this chemical methodology are still important challenges. In this context, new dimeric TBQs have been synthesized by wet chemical protocols for their further use in the synthesis of double-strand oligomers. Interestingly, the new systems exhibit many defects, due to the intrinsic nature of the synthesized precursors.[3]
In this work, we firstly take advantage of the introduction of heteroatoms at the edges of the monomers in order to grow 1D new π-conjugated polymers which, eventually, collapse into amazing large 2D networks by non-covalent interactions. Moreover, when suitable designed TBQs with both the presence of heteroatoms and steric hindrance, unprecedented 1D and covalently linked 2D π-conjugated polymers are formed. These results have allowed the study of new topologically non-trivial polymers which will be presented and discussed in this communication.
[1] Cirera, B., Sánchez-Grande, A., de la Torre, B., Santos J. et al. Nat. Nanotechnol.
2020, 15, 437–443.
[2] González-Herrero, H., Mendieta-Moreno, J. I., Edalatmanesh, S., Santos, J. et al. Advanced Materials
2021, 33, 2104495.
[3] Vicent, D. J., Perez-Escribano, M. et al.
Chem. Sci., 2023, 14, 10112-10120.
Localized Corrosion Behavior and Corrosion Microstructure of LZ91 and LAZ931 Mg Alloys
Authors: Fu Ya-Han , Pan Shi-Yuan , Su Te-Cheng , Chu Peng-Wei 
Published: August 2024

LZ91 (Mg-9 wt%Li-1 wt%Zn) and LAZ931 (Mg-9 wt%Li-3 wt%Al-1 wt%Zn) alloys are emerging ultra-lightweight Mg alloys, which can be used in applications that require weight reduction. Although LZ91 alloy has found some success in the 3C industry, the relatively inferior mechanical strength limits its widespread application. To improve the mechanical properties, Al was added to LZ91 alloy to form LAZ931 alloy. However, both LZ91 and LAZ931 alloys are primarily composed of a dual-phase structure with α (HCP) and β (BCC) phases, which form a microgalvanic couple in the corrosion environment. Furthermore, adding Al introduces additional secondary phases, such as AlLi and MgLi2Al, which complicate the corrosion behavior and mechanism. Therefore, this study investigates the corrosion behavior and microstructure of LZ91 and LAZ931 Mg alloys in 3.5 wt% NaCl solution and the relationships to the phase distribution in the alloy substrates.
By in situ optical microscope (OM) observations and open circuit potential (OCP) monitoring, localized corrosion initiates on the LAZ931 alloy earlier than on the LZ91 alloy. The early initiation and propagation of localized corrosion on the LAZ931 alloy result in worse corrosion resistances and faster corrosion rates measured by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves. By scanning Kelvin probe force microscopy (SKPFM), the Li-rich β phase is more active than the Mg-rich α phase. However, interestingly, localized corrosion was found to preferentially propagate inside the α phase, which seems to contradict the SKPFM measurements. The preferential propagation of localized corrosion in the α phase could be related to the difference in the surface corrosion film thicknesses on the α and β phases before localized corrosion propagation. The localized corrosion behavior and corrosion microstructure of the alloys will be discussed based on electrochemical measurements and site-specific microstructure characterizations.

Figure 1
Exploring the Kinetics of Oxygen Reduction Reaction in Relation to Pitting Corrosion Resistance in Fe-Cr Alloys
Authors: Wang Ying , Blackwood Daniel John 
Published: August 2024

Pitting corrosion, a major concern in materials science and engineering, threatens critical metallic structures and components. Its implications reach across daily life and industries such as energy, transportation, and infrastructure, potentially causing environmental harm, economic losses, and even loss of life. This complex process is influenced by factors including material composition, local environment, and mechanical stresses.1 Once initiated, pit propagation rates are largely dependent on the magnitude of the supporting cathodic current available from the oxygen reduction reaction (ORR) occurring on the external passive film.2 In Fe-Cr alloys, the ORR occurs on this film, undergoing a mixed diffusion and kinetic-controlled process. The number of electrons involved and the corrosion rate are determined by the thermodynamically stable state of the passive film.
This research studies the ORR kinetics on FeCr alloys fabricated by arc-melting, using both computational and experimental methods. The rotating disc electrode technique was employed across various Fe:Cr alloys in alkaline and neutral electrolytes. The Koutecky-Levich analysis showed a dominant four-electron ORR pathway in all tested Fe-Cr alloys, with the ORR significantly inhibited by higher proportions of Cr2O3 in the film, suggesting a correlation with high chromium content. Experimental ORR overpotentials, when combined with theoretical potential-pH (Pourbaix) diagrams, helped discern the likely characteristics of the passive films on the alloys. It was deduced that the catalytic properties of potential passive films increased in the order Cr2O3 < Fe3O4 < Fe2O3 < FeCr2O4. These findings, excellently aligned with density functional theory (DFT) modelling, underscore the role of increased chromium levels in slowing pitting progression by suppressing the ORR.
In summary, this research offers distinctive insights into the correlation between the kinetics of the ORR and the resistance to localized corrosion in Fe-Cr alloys, which enhances our understanding of the underlying mechanisms of pitting corrosion.

Keywords

FeCr alloy, pitting corrosion, ORR, rotating disc electrode, DFT

Reference

[1] B. Zhang, J. Wang, B. Wu, X. W. Guo, Y. J. Wang, D. Chen, Y. C. Zhang, K. Du, E. E. Oguzie, and X. L. Ma, Nat. Commun. (2018) 9, 2559.
[2] G. T. Burstein, P. C. Pistorius, and S. P. Mattin, Corros. Sci. (1993) 35, 57.
Modeling Silver Corrosion Mechanisms in Marine Atmospheric Environments
Authors: Policastro Steven A , Sanders Christine E. , Johnson Alexander , Santucci Raymond J , Hammond Mark H. 
Published: August 2024

Measures that can assess the severity of the local environment are an important tool for combating atmospheric corrosion. One approach for determining the environmental severity employs electrochemical analysis alongside surface characterization on silver coupons exposed to the environment for varying durations. However, despite the long use of silver as an environmental severity monitor, the underlying reaction mechanisms that give rise to the observed corrosion products are not well understood. In addition, the measured ratios of silver corrosion products appear to be unique to the location where the silver coupons were exposed.
The goal of this work is to develop models of silver oxidation reactions that can explore pathways for the formation of silver corrosion products. We use density functional theory (DFT) calculations in nudged elastic band (NEB) approximations to determine electrochemical and chemical reaction along with surface diffusion energy barriers. An example reaction is shown in Figure 1a and b, in which an O2 molecule is adsorbed on an ‘on-top’ site on a relaxed Ag (100) crystal structure with periodic boundary conditions in the x and y-planes. The O2 molecule then dissociates into individual O atoms. The reaction pathway is approximated using the NEB approach to determine the dissociation energy barrier in Figure 1c. These reaction energy barriers are incorporated into a kinetic Monte Carlo (KMC) model of silver reactions to estimate the corrosion products present in marine atmospheric environments for comparison with experimental data.

Figure 1
(Invited) Model-Based BMS for Current and Next-Generation Batteries
Authors: Subramanian Venkat R. 
Published: August 2024

Fast charging is researched heavily for the widespread implementation of lithium-ion batteries for electric vehicles. However, charging at high currents accelerates several parasitic reactions that lead to the degradation of the cell, affecting its lifetime. These reactions lead to loss of lithium inventory, loss of active material, and increased impedance in the cell. Examples of these side reactions include the growth of the solid-electrolyte interphase (SEI) layer, transition metal dissolution and deposition, lithium plating, solvent oxidation, etc. These mechanisms degrade the cell and reduce its cycle life.
Physics-based multi-scale battery models solve for equations that govern the charge and mass balances within the cell. Using these detailed mathematical models, it is possible to study material degradation mechanisms and predict their impact on capacity loss under several operating conditions. These models can be used to design new batteries with appropriate materials and design parameters suited for any given purpose.
More critically, these models can be integrated with battery management systems (BMS) to control the cell’s performance. These models can further be used to design novel charging protocols that enable safe and optimal cell performance and suppress cell material degradation. The BMS monitors and maintains the voltage, current, and temperature and estimates the internal states of the cell. Model-based BMS algorithms require fast codes that can predict and estimate battery parameters in real-time and control the battery’s performance under different loads.
Currently, the BMS implements equivalent circuit models that inadequately predict the cell’s performance for various conditions and design parameters. This talk presents the current efforts to move the models for BMS for current and next-generation batteries for single-cell to pack-level simulations.

Figure 1
CMP: Four Decades of Innovation and a Promising Future
Authors: Canaperi Donald 
Published: August 2024

The invention of CMP by IBM in 1983 represents an inflection point in the evolution of semiconductors. It was a bold and risky idea to mechanically apply abrasives to the surface of a wafer, but this new process for restoring a wafer to a planar state was the key to continued areal scaling and increased device complexity. Initially applied to a simple application for filling trenches with insulator, the potential of this technique was evident. Through understanding of material properties and subsequent manipulation of slurry chemistry, CMP was applied to enable the more challenging and technically critical processes for Shallow Trench Isolation and Tungsten contacts. The late 1990’s saw the introduction of copper interconnects. IBM was first to market this technology which continues to support conductors down to lines widths on the order of 10 nanometers! The CMP process required for copper interconnects demanded a thorough understanding of the materials present and potential surface phenomena for exploitation. For this need, a new and complex mechanism for copper planarization was invented. Equally challenging was the need for a subsequent non-selective barrier removal step. For this a unique, self-balancing approach was also invented, borrowing some elements from previous STI technology.
Device architecture has progressed from planar geometry to FINFETs to Gate All Around, or Nanosheet technology. This evolution has required increasingly more CMP process steps with a concurrent demand for increased process control. Gate height control for Nanosheeets is currently paramount for performance, affected by many CMP steps in the process flow. A typical requirement is less than 1nm added variability per CMP step!
Looking forward, CMP continues to be tapped to enable technology evolution. Polish steps are becoming part of the patterning process to enable pitch splitting for upcoming nodes. A VTFET integration approach can enable further area scaling but presents integration challenges; CMP is being asked to enable “third color” schemes for the protection of NFET vs PFET devices which is necessary at various points in the in the VTFET process flow. Heterogeneous Integration is demanding nanometer control of topography across large contact pads and large lateral distances. Finally, extreme scaling is creating fundamental challenges for metal polish at the contact and interconnect levels. CMP tool architecture currently does not provide for control of ambient conditions at the wafer surface during wet transport and post CMP cleaning. Subsequently, unwanted metal dissolution is observed. New tool designs will be needed to control wafer surface conditions, and particularly oxygen exposure through all steps within the CMP tool.

This talk is dedicated to the special session in honor of Professor S.V. Babu
(Invited) Doping Mechanisms and Defect Passivation of p-Type SnOx for Tfts and Bipolar Devices
Authors: Lee Dong Hun , Song Han Wook , Lee Sunghwan 
Published: August 2024

Despite the outstanding achievements in multiple areas such as displays and energy, oxide electronics has been limited to single-polar (n-type) applications due to the facile generation of oxygen vacancies as native donors. On the contrary, the processing of p-type oxides is restrained due to the high formation energy of native acceptors. Furthermore, the oxygen 2p orbitals of the majority of oxide semiconductors are anisotropic and localized to the valence band maximum (VBM), resulting in a large effective mass of holes and hence low carrier mobility.
Hybrid orbital electronic configurations with cation d10 (closed shell structure) and cation s2 (pseudo-closed structure) have been suggested initially in complex oxides (e.g., CuMO2 where M= Al, Ga, and In; and SrCu2O2) to delocalize the oxygen 2p orbitals from the VBM. However, these complex oxides require high temperatures to process and are difficult to engineer the electrical properties of carrier density and carrier mobility due to the correlated nature of multi-cation species. Several single-cation p-type oxides such as PbO, Bi2O3, and SnO have emerged as well, where the energy level of a unique s-orbital of cations is similar to oxygen 2p orbitals, forming strong hybrid structures. In addition, a simpler single-cation structure leads to easier control of electrical properties required in practical device applications such as thin film transistors (TFT) and complementary logic inverters.
We previously reported scalable processing of p-type SnOx through thermodynamic-based interfacial reactions as well as reactive sputtering.1 More recently, we also suggested multi-modal encapsulation to enhance TFT on- and off-state behaviors and identified a defect complex as an effective p-type doping agent.2 However, challenges remain since the TFT off-state current is large, and the defect/trap state density is high.
In this presentation, we share our approaches to engineer the off-state current and passivate the defect/trap states. In addition to channel thickness optimization, intrinsic (Sn vacancy or oxygen interstitial) and extrinsic (H-related species) doping strategies to adjust channel carrier density will be compared. The performance of several surface treatments (oxygen plasma and UV) and TFT back channel encapsulations (SiO2 and Al2O3) will be systematically compared. Then, the device performance of optimized p-type SnO TFTs and complementary inverters with n-type InZnO TFTs will be discussed.
References

Lee et al., ACS Applied Materials & Interfaces, 13 (46), 55676–55686 (2021)

Lee et al., ACS Applied Materials & Interfaces, 14 (48), 53999–54011 (2022)

Acknowledgments
This work was partially supported by National Science Foundation, Award number ECCS-1931088 and CBET-2207302.
(Invited) Nitrogen Based Solid State Magneto-Ionics
Authors: Jensen Christopher , Chen Zhijie , Quintana Alberto , Quarterman Patrick , Grutter Alexander , Balakrishnan Purnima , Zhang Huairuo , Davydov Albert , Liu Chen , Zhang Xixiang , Liu Kai 
Published: August 2024

Solid-state magneto-ionic (MI) effects have shown promise for energy-efficient nanoelectronics, where ionic migration may be used to achieve atomic-scale control of interfaces in magnetic nanostructures. To date, magneto-ionics have been mostly explored in oxygen-based systems [1-4], while there is a surge of interest in alternative ionic systems due to their different ionic migration mechanisms and characteristics [5-7].
We have recently demonstrated effective MI control of magnetic functionalities using a variety of ionic species, particularly nitrogen. In nitride-based Ta/CoFe/MnN/Ta films, the chemically induced MI effect is combined with the electric field driving of nitrogen to electrically manipulate exchange bias [8]. Upon field-cooling the heterostructure, ionic diffusion of nitrogen from MnN into the Ta layers occurs. A significant exchange bias is observed, which can be further enhanced by ~ 20% after voltage conditioning (Figs. 1a-1e). This enhancement can be reversed by voltage conditioning with an opposite polarity. Nitrogen migration within the MnN layer and into the Ta capping layer causes the enhancement in exchange bias, which is observed in polarized neutron reflectometry studies.
We have also achieved all-nitride-based magneto-ionic systems [9]. Thin films of (001)-ordered Mn4N are grown by sputtering Mn onto Mn3N2 seed layer on Si (100) substrate. Nitrogen ion migration across the Mn3N2 /Mn layers leads to a continuous evolution of the layers to Mn3N2 /Mn4N, Mn2N/Mn4N, and eventually Mn4N alone (Figs. 1f-1g). Furthermore, we have demonstrated MI control of the exchange bias effect in an all-nitride Mn4N/MnNx system, where the field-trained exchange field can be varied up to ten times by introducing or extracting nitrogen from the nitride system. This is achieved by adjusting the nitrogen gas partial pressure during deposition or varying annealing temperature after deposition.
These effects demonstrate contrasts with oxygen-based MI effects in terms of operating principles, switching speed, and reversibility. Such MI systems are valuable platforms to gain quantitative understanding at buried interfaces. They also offer potentials for device applications based on electric modulation of magnetic functionalities.
This work has been supported in part by the NSF (ECCS-2151809, DMR-2005108, DMR-1828420), SRC/NIST SMART Center, and KAUST.
[1] U. Bauer et al., Nat. Mater. 14, 174 (2015).
[2] C. Bi et al., Phys. Rev. Lett. 113, 267202 (2014).
[3] D. A. Gilbert et al., Nat. Commun. 7, 11050 (2016).
[4] G. Chen et al., Sci. Adv. 6, eaba4924 (2020).
[5] A. J. Tan et al., Nat. Mater. 18, 35 (2019).
[6] G. Chen et al., Phys. Rev. X 11, 021015 (2021).
[7] J. de Rojas et al., Nat. Commun. 11, 5871 (2020).
[8] C. J. Jensen et al., ACS Nano 17, 6745 (2023).
[9] Z. J. Chen et al., Appl. Phys. Lett. 123, 082403 (2023).

Figure 1
(Invited) Epitaxial III-V Nanomaterials on the Si Platform for Quantum and Data Communications
Authors: Lewis Ryan B. 
Published: August 2024

As Si-based integrated photonic components begin to replace older technologies for optical data communications, the need for better integration of semiconductor lasers on the Si platform is greater than ever. In addition, emerging interest in integrated-photonic-based quantum computing and quantum sensing presents a further need for quantum light emitters—entangled and single-photon—on Si. III-V quantum dots represent a promising solution, both for the active region of telecommunications-wavelength lasers and for quantum emitters. However, epitaxial quantum dots grown on conventional (100) substrates typically lack the high symmetry required for entangled-photon emission.
This presentation will discuss our recent work to develop a novel approach for III-V direct growth on Si via an ultrathin (<10 nm) single crystal strain relieving buffer layer, realized by the selective oxidation and condensation of an amorphous SiGe surface layer. The fabrication and properties of this novel Ge-rich buffer layer, as well as its use for subsequent III-V organometallic vapor-phase epitaxy will be presented.
The second part of the talk will present our recent work on the epitaxial growth and characterization of (In,Ga)As quantum dots for the above-mentioned applications. Specifically, I will show that surface-energy-modifying surfactants (Sb, Bi) present the possibility to externally direct quantum dot formation “on-demand” in strained InAs layers on GaAs(111) substrates, where quantum dot formation by the Stranski–Krastanov process does not naturally occur. These nanostructures are prospective for high-symmetry entangled-photon emitters. The three-dimensional (3D) composition profile of InAs quantum dot layers is characterized by atom-probe microscopy (APT), elucidating the real-world quantum dot matrix. This 3D composition data is input into a finite element solver to determine the quantum dot energies and wavefunctions for electrons and holes. The modeling reveals that in high-density quantum dot layers, the electron and hole states are hybridized between multiple quantum dots in the matrix. This has important consequences for design of quantum dot light emitters. The predicted transition energies are in agreement with low-temperature photoluminescence. This work constitutes a promising approach for integrating telecommunications-wavelength quantum dot lasers and entangled photon emitters on the Si integrated photonics platform.