Structural Uniformity Research Articles

Self-assembled ferritin-based nanoparticles elicit a robust broad-spectrum protective immune response against SARS-CoV-2 variants

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its variants has resulted in global economic losses and posed a threat to human health. The pandemic highlights the urgent need for an efficient, easily producible, and broad-spectrum vaccine. Here, we present a potentially universal strategy for the rapid and general design of vaccines, focusing on the design and testing of omicron BA.5 RBD-conjugated self-assembling ferritin nanoparticles (NPs). The covalent bonding of RBD-Fc to protein A-ferritin was easily accomplished through incubation, resulting in fully multivalent RBD-conjugated NPs that exhibited high structural uniformity, stability, and efficient assembly. The ferritin nanoparticle vaccine synergistically stimulated the innate immune response, Tfh-GCB-plasma cell-mediated activation of humoral immunity and IFN-γ-driven cellular immunity. This nanoparticle vaccine induced a high level of cross-neutralizing responses and protected golden hamsters challenged with multiple mutant strains from infection-induced clinical disease, providing a promising strategy for broad-spectrum vaccine development for SARS-CoV-2 prophylaxis. In conclusion, the nanoparticle conjugation platform holds promise for its potential universality and competitive immunization efficacy and is expected to facilitate the rapid manufacturing and broad application of next-generation vaccines.

A Chemical Safety Assessment of Lyocell-Based Activated Carbon Fiber with a High Surface Area through the Evaluation of HCl Gas Adsorption and Electrochemical Properties

This study investigates lyocell-based activated carbon fibers (ACFs) for their suitability in adsorbing and electrochemically detecting toxic HCl gas. ACFs were prepared via steam activation, varying temperature (800–900 °C) and time (40–240 min) to assess their adsorption and sensing capabilities. The adjustment of activation temperature and reaction time aimed to regulate the uniformity of the pore structure and pore size of the active reaction area, as well as the number of reaction sites in the ACFs. Optimal ACFs were achieved at 900 °C for 50 min, exhibiting the highest specific surface area (1403 m2/g) and total pore volume (0.66 cm3/g). Longer reaction times resulted in pore formation and disorder, reducing mechanical strength. The ACFs prepared under optimal conditions demonstrated a rapid increase in resistance during sensor measurement, indicating a significant sensitivity to HCl gas. These findings suggest the potential of ACFs for efficient HCl gas adsorption (1626.20 mg/g) and highlight the importance of activation parameters in tailoring their properties for practical applications.

Effects of rock water with different acidity on microstructure and reburning ability of residual coal in goaf

To explore the influences of rock water acidity (PH = 4,5,7) over the microstructure and reburning behaviors of oxidized residual coal in the overlying goaf, the pore morphology, coal surface, functional group content and activity of pre-oxidized coal (O0) and water-immersed oxidized coal (OI) were analyzed by Low-temperature nitrogen adsorption and In-situ diffuse reflection experiments, combining with fractal dimension theory and functional group oxidation kinetics. The oxidation and reburning ability of coal samples has been analyzed by Thermogravimetric-Differential thermal analysis experiment. The results are as follows: Part of the type-III pores of pre-oxidized coal become type-II pores when immersed. The acidic solution has stronger corrosivity to O0 than distilled water, playing a role in smoothing coal and improving the uniformity of pore structure. The order of reburning ability of samples is OI7>OI4>O0>OI5 according to the ignition and stage average mass loss rate (RM). The reactivity of –OH may affect the reburning ability of coal more than its initial content. Soaking is beneficial to the decrease of activation energy of aliphatic groups, and the activity of –C=O- and -C-O- in acid-soaked coal molecules is stronger, so that they can take part in coal-oxygen composite reactions at low temperature.

A highly homogeneous electrorheological fluid with potential applications in optics

A new type of electrorheological fluid (ERF) with high ER efficiency, low zero-field viscosity and high uniformity was synthesized by a hydrolysis method, based on modified titanium and succinic acid. The electro-responsive performance of ERF under electric field 0–3 kV mm−1 were studied in detail. In addition to traditional research methods to explore the morphology of the ER particles, we also utilized optical diffraction imaging to study the uniformity of the chain-like structure formed by the ER particles. Due to the relatively uniform size, the particles aggregate into a periodic spatial modulation structure parallel to the electric field direction and similar to a grating on the macroscopic scale, which can further manufacture liquid controllable gratings. The observed diffraction spots, up to six levels, indicate the ERFs have potential applications in the field of optics.

Regularized cost function in wavefront shaping for advancing the contrast of structured light.

The cost function in the iterative optimization algorithms is one of the sensitive optimization controllers that plays a crucial role in feedback based wavefront shaping for constructing well-resolved complex structured light through scattering media. There has been a trade-off between resolution and the contrast enhancement of the structured light in wavefront shaping. We have developed an ℓ 2-norm based quadratic cost function (L2QN) and proposed a regularized cost function (RCF) for advancing the contrast and maintaining the high resolution of structured light. Both the simulations and experiments have been performed, and it has been found that the proposed RCF significantly advances the contrast and structural uniformity for focusing light through scattering media as well as for diffused reflection mode. The potential applications of the method demonstrated in this study can be extended into holographic displays, structured light illumination microscopy, photo-lithography, photothermal treatments, dosimetry, laser materials processing, and energy control inside and outside an incubation system.

Unsymmetrical Low-Generation Cationic Phosphorus Dendrimers as a Nonviral Vector to Deliver MicroRNA for Breast Cancer Therapy.

The development of nonviral dendritic polymers with a simple molecular backbone and great gene delivery efficiency to effectively tackle cancer remains a great challenge. Phosphorus dendrimers or dendrons are promising vectors due to their structural uniformity, rigid molecular backbones, and tunable surface functionalities. Here, we report the development of a new low-generation unsymmetrical cationic phosphorus dendrimer bearing 5 pyrrolidinium groups and one amino group as a nonviral gene delivery vector. The created AB5-type dendrimers with simple molecular backbone can compress microRNA-30d (miR-30d) to form polyplexes with desired hydrodynamic sizes and surface potentials and can effectively transfect miR-30d to cancer cells to suppress the glycolysis-associated SLC2A1 and HK1 expression, thus significantly inhibiting the migration and invasion of a murine breast cancer cell line in vitro and the corresponding subcutaneous tumor mouse model in vivo. Such unsymmetrical low-generation phosphorus dendrimers may be extended to deliver other genetic materials to tackle other diseases.

Uniformly scalable and stackable porous transport layer manufactured by tape casting and calendering for efficient water electrolysis

Proton exchange membrane water electrolysis (PEMWE) stands out as the most promising and eco-friendly technology for directly converting renewable energy into hydrogen. A critical element within a PEMWE cell is the porous transport layer (PTL), typically constructed from Ti to withstand the rigorous conditions of water electrolysis. Herein, we present a cost-effective and viable fabrication process for Ti-PTLs, utilizing tape-casting method in combination with a lamination-roll calendering procedure, facilitating precise thickness control. By systematical fine-tuning the debinding conditions, we obtained a phase-pure Ti-PTL endowed with a highly-interconnected pore structure. A comprehensive analysis of digitally twinned Ti-PTL, constructed through a state-of-the-art three-dimensional (3D) reconstruction process, reveals a remarkable uniformity in the open pore structures across Ti-PTLs of varying thicknesses, highlighting their considerable practical potential. Furthermore, the electrochemical performance of PEMWE cells using our Ti-PTLs surpassed that of the benchmark commercial Ti-PTL, demonstrating the significant promise of our tape-casting process followed by lamination-roll calendering procedure in practical Ti-PTL fabrication.

NBN/BNB-doped phenalenyl homo- and heterodyads: structural uniformity but optoelectronic diversity

Phenylene-bridged homo- and heterodyads of NBN- and BNB-phenalenyls were synthesized. The heterodyads show ambipolar redox character and aggregation-induced emission in the solid state.

Fabrication of a high performance flexible capacitive porous GO/PDMS pressure sensor based on droplet microfluidic technology.

Porous structures are an effective way to improve the performance of flexible capacitive sensors, but the pore size uniformity of porous structures is not easily controlled by current methods, which may affect the inconsistent performance of different batches of sensors. In this paper, a high performance capacitive flexible porous GO/PDMS pressure sensor was prepared based on droplet microfluidic technology. By testing the performance of the sensor, we found that the sensor with a flow rate ratio of 1 : 3 has relatively good performance, with a degree of hysteresis (DH) of 8.64% and a coefficient of variation (CV) of 5.2%. Therefore, we studied the sensor performance based on this process. The result shows that the sensitivity of the flexible capacitive porous GO/PDMS pressure sensor reached 0.627 kPa-1 at low pressure (0-3 kPa), which is significantly higher than that of the pure PDMS thin film sensor (about 0.031 kPa-1) and the porous PDMS pressure sensor (0.263 kPa-1). At the same time, the sensor has a large range with a fast response time of 240 ms and a relaxation time of 300 ms at 30 kPa and an ultra-low detection limit (70 Pa). It can maintain stable operation under continuous force loading/unloading cycles and can respond well to different pressure step changes, so the sensor can be used to detect the movement process of each finger, knee, foot and other joints of the human body. In conclusion, the droplet microfluidic technology can effectively prepare high-performance capacitive flexible porous GO/PDMS pressure sensors.

The influence of the molecular chain length of PVA on the toughening mechanism of calcium silicate hydrates.

In recent years, polymers have been demonstrated to effectively toughen cementitious materials. However, the mechanism of interaction between the polymers and C-S-H at the nanoscale remains unclear, and the quantitative impact of the polymer chain length on toughening effectiveness is lacking in research. This study employs molecular dynamics techniques to examine the impact of the polyvinyl alcohol (PVA) chain length on the tensile performance and toughening mechanism of C-S-H. The toughening effect in both the X and Z directions exhibits an initial enhancement followed by a decline with increasing chain length. The optimal degrees of polymerization are determined to be 8 and 12 in the X and Z directions, respectively, resulting in an improvement of fracture energy by 146.7% and 29.5%, respectively. During the stretching process along the X and Z axes, the chain length of PVA molecules significantly influences the variation in the number of Ca⋯O bonds in the system, leading to different stress responses. Additionally, PVA molecules form C-O-Si bonds with the silicate layers of C-S-H, bridging the adjacent layers in a left-right or up-down manner. The toughening effect of PVA on C-S-H depends on the behavior of PVA molecules with different chain lengths, and there exists an optimal range of chain length for PVA, enabling it to enhance structural uniformity and adjust its own conformation to absorb strain energy. When the length of PVA molecular chains is too short, it can easily cause stress concentration in the system and its connection with silicates is not significant. Conversely, when the length of PVA molecular chains is too long, the large molecular structure restricts its extension in the defects of C-S-H, and as the stretching progresses, PVA molecules break and form numerous small segments, thereby losing the advantage of the chain length. This study provides a theoretical basis for the ability of polymers to toughen cementitious materials.

High Emissivity MoSi2-SiC-Al2O3 Coating on Rigid Insulation Tiles with Enhanced Thermal Protection Performance.

High emissivity coatings with sol as the binder have the advantages of room temperature curing, good thermal shock resistance, and high emissivity; however, only silica sol has been used in the current systems. In this study, aluminum sol was used as the binder for the first time, and MoSi2 and SiC were used as emittance agents to prepare a high emissivity MoSi2-SiC-Al2O3 coating on mullite insulation tiles. The evolution of structure and composition at 1000-1400 °C, the spectral emissivity from 200 nm to 25 μm, and the insulation performance were studied. Compared with the coating with silica sol as a binder, the MoSi2-SiC-Al2O3 coating has better structural uniformity and greater surface roughness and can generate mullite whiskers at lower temperatures. The total emissivity is 0.922 and 0.897, respectively, at the wavelength range of 200-2500 nm and 2.5-25 μm, and the superior emissivity at a low wavelength (<10 μm) is related to a higher surface roughness and reduced feature absorption. The emissivity reduction related to the oxidation of emittance agents at a high temperature (-10.2%) is smaller than that of the silica-sol-bonded coating (-18.6%). The cold surface temperature of the coated substrate is 215 °C lower than the bare substrate, suggesting excellent thermal insulation performance of the coating.

The Social Foundations of Academic Freedom: Heterogeneous Institutions in World Society, 1960 to 2022

This article analyzes academic freedom worldwide with newly available cross-national data. The literature principally addresses impingements on academic freedom arising from religion or repressive states. Academic freedom has broadly increased since 1945, but we see episodic reversals, including in recent years. Conventional work emphasizes the uniformity of international institutional structures and their influence on countries. We attend to the heterogeneity of international structures in world society and theorize how they contribute to ebbs and flows of academic freedom. Post-1945 liberal international institutions enshrined key rights and norms that bolstered academic freedom worldwide. Alongside them, however, illiberal alternatives coexisted. Cold War communism, for instance, anchored cultural frames that justified greater constraints on academia. We evaluate domestic and global arguments using regression models with country fixed effects for 155 countries from 1960 to 2022. Findings support conventional views: academic freedom is associated positively with democracy and negatively with state religiosity and militarism. We also find support for our argument regarding heterogeneous institutional structures in world society. Country linkages to liberal international institutions are positively associated with academic freedom. Illiberal international structures and organizations have the opposite effect. Heterogeneous institutions in world society, we contend, shape large-scale trajectories of academic freedom.

(Invited) Nucleation, Growth and Location Regulation of Heterogeneous Catalysts Synthesized by Atomic Layer Deposition

For supported catalysts, the particle surface or metal-support interface and its vicinity are the main areas providing active sites. In this regard, surface and interface engineering of heterogeneous catalysts is effective and critical for optimizing their catalytic performances. During the formation of active components, the structural uniformity, stability and location of nucleation sites determine the structural and scale uniformity, stability and environmental consistency of active sites, and ultimately determine their catalytic performance. Therefore, the regulation of nucleation, growth and location of active components is the key to precisely regulate the surface and interface structure and properties of supported catalysts. However, traditional preparation methods (such as impregnation method and precipitation method) have limitations in precise regulation of particle size, location and microstructure of catalysts due to the surface heterogeneity of supports and the high surface energy of nanoparticles, which makes it difficult to reliably reveal the structure-activity relationship of the catalyst. Therefore, the development of advanced fabrication methods is of vital significance to realize the nucleation, growth and location regulation of heterogeneous catalysts at atomic level precision. Atomic layer deposition (ALD) is a powerful scientific tool for catalytic research due to its self-limiting, atom-by-atom growth features. However, there is still a lack of rational knowledge of the nucleation and growth mechanism of catalytic particles prepared by ALD, the microscopic mechanism of interface structure modification, and the catalytic reaction mechanism. This is the topic of this lecture, in which we discuss the latest progress made in our group in precisely regulating the microstructure, size and location of ALD-deposited active components by several effective methods including nucleation site engineering, deposition kinetics engineering and template-assisted ALD method, as well as elucidating the nucleation and growth mechanism of ALD-deposited active components by in-situ and operando XAFS characterization based on our designed and built ALD-XAFS device. Through the above works, the nucleation and growth mechanisms of the deposited species and modification species, the microscopic mechanism of interface structure modification, and the influence of the size effect, the interface effect, and the distance effect on the catalytic performance were clarified. The structure-activity relationship was understood at the atomic/molecular level. These works will provide new ideas and scientific basis for the catalyst design and the performance regulation.

Acceleration of Wound Healing Process Using Lactoferrin by Stimulating Proliferation of Fibroblasts in Wistar Rats (Rattus Novergicus): In Vivo Method

Wound is disruptions in the uniformity of body tissue structure, including the outermost layer from the skin to the internal organs, parts of fat, muscles, bones, and others. To address this issue, lactoferrin is a bioactive compound with promising benefits, playing a crucial role in wound healing by enhancing fibroblasts migration and proliferation, as well as collagen synthesis. Moreover, when used in wound therapy, lactoferrin induces a decrease in pro-inflammatory cytokines production by macrophages with an increase in the expression of VEGF and FGF-2. This study aimed to determine the role of lactoferrin in accelerating in vivo incision wound healing in Wistar rats and to prove the correlation between fibroblasts and collagen. This study adopted a laboratory experimental design using a post-test only control group with 28 samples. The samples were divided into the control, and three experimental groups, each treated with two drops of Lactoferrin (Shaner Whey Protein) at 20 mg/ml, 40 mg/ml, and 80 mg/ml. Each sample was observed for an increase in fibroblasts proliferation and density of collagen fibers. Lactoferrin concentration of 80 mg/ml had the most effect on increasing the number of fibroblasts and collagen with a significant value &gt; 0.05, using a posthoc test. Lactoferrin concentration of 80mg/ml showed the most significant results, showing a significant acceleration in wound healing process.

Influence of Increasing Deposition Temperature during Atomic Layer Deposition on Electrical Properties and Reliability in Al2O3 - Doped ZrO2 Based Two-Dimensional and Three-Dimensional Metal-Insulator-Metal Decoupling Capacitors

The influence of deposition temperature (TD) on thin film layers of high-k dielectrics used as insulators in embedded Metal-Insulator-Metal (MIM) decoupling capacitors is critical to their future behavior in terms of electrical properties and reliability. These layers are deposited via atomic layer deposition (ALD), which is known for its high uniformity in any type of structural topology. High-k dielectrics, such as Zr, inside high aspect ratio three-dimensional (3-D) structures are a challenging task even in the case of ALD processing. Al2O3 doping is often used within the high-k layer stack during ALD to optimize electrical performance of MIM structures with respect to leakage currents and reliability. In this context, appropriate atomic layer deposition temperature (TD) of the Al2O3-doped ZrO2 high-dielectric stack must be established to enable optimum electrical properties. Electrical data of decoupling capacitors must fulfill the industrial requirements, which demand that, for example, the leakage current density (J) must not exceed a certain level (<1µA/cm²) and that long-term lifetimes under different operating temperatures of a minimum of 10 years at accumulated fail rate of 10 ppm must be achieved.In this work, we report on a study of the influence of ALD TD on Al2O3-doped ZrO2 thin films fabricated on 300mm wafers. We evaluate the impact of TD on high aspect ratio substrates based on electrical properties and reliability parameters. To achieve this, we use 3 different deposition temperatures (293°C, 313°C, and 333°C) and two physical topologies (planar and 3-D capacitors with cavities-trenches) without compromising the chemical stability of the ALD precursors. For metal precursors, TEMAZ (Tetrakis-ethylmethylamino-zirconium) and TMA (Tri-methyl-aluminum) are used for Zr and Al, respectively. Ozone is used as reactant agent and argon as carrier/purge gas. The ZrO2 cycle consists of pulsing with TEMAZ, purging with Ar gas, oxidizing with O3, and purging with Ar gas. In a similar way, the dopant (TMA) is added, followed by purging steps with Ar, O3 and Ar again. After a few ZrO2 cycles, an Al2O3 cycle is followed, so that nano-laminate films of Al2O3 are formed on top of ZrO2 films. By repeating the ZrO2 and the Al2O3 cycles several times, the desired film thickness is achieved. For the MIM stacks, TiN is used as an electrode material on both sides. There was no post deposition anneal to maintain the amorphous state of the insulator with low defect density and high structural uniformity.The planar capacitors show minimal changes in terms of capacitance density with increasing TD. On the other hand, the 3-D samples show a 17% increase in capacitance density with a TD increase of 20°C from 293°C to 313°C. This increase becomes much smaller (2.3%) for a further TD increase of 20°C at 333°C. However, with increasing TD, the E-field linearity of 3-D samples, expressed by the quadratic E-field capacitor coefficient α, increases by 2% and 17% for TD=313°C and TD=333°C, respectively. The significant improvement in field linearity indicates the highest TD provides the best and most stable capacitance behavior. The J(E)-curves of planar and 3-D devices exhibit different behavior with respect to current density and dielectric breakdown. Specifically, planar devices show greater variation in J(E)-curves over temperature, with decreasing breakdown field (EBD) as TD increases. On the other hand, 3-D samples show little variation in EBD with temperature. Furthermore, planar devices show lower symmetry in their J(E)-curves over the field polarity compared to 3-D capacitors, which could be attributed to differences in conduction mechanisms. Despite having a lower EBD, planar devices reveal improved lifetime and reliability with increasing TD, possibly due to reduced carbon impurities during the insulator deposition. For instance, increasing TD from 293°C to 313°C leads to a 47% improvement in extrapolated lifetime, while a further increase in TD, improves lifetime by an additional 14%. A 10-year lifetime goal can only be achieved at 1MV/cm with TD=333°C and for samples exposed to any temperature conditions (25-150°C). In contrast, 3-D capacitors exhibit a better degradation slope at lower deposition temperatures but require the highest TD to achieve an 18% improvement in lifetime. However, due to their lower EBD, they cannot reach the 10-year lifetime goal at 1MV/cm, except at low applied temperatures (25°C-50°C).In conclusion, the highest TD of 333°C without any chemical decomposition of the metal precursor (TEMAZ) is the optimal deposition temperature for both planar and 3-D Al2O3-doped ZrO2 based MIM decoupling capacitors, providing auspicious results in terms of all relevant parameters. Figure 1

Effect of zirconium content on defect structure and optical uniformity of dysprosium-doped lithium niobate crystals

Four Zr: Dy: LiNbO3 crystals doped with different concentrations of Zr4+ (0, 1, 2, 4, mol%) have been grown by Czochraski technique. The effect of doping concentration of Zr4+ ions on the actual concentration of Zr4+ and Dy3+ ions in doped crystal was studied by the inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results of X-ray diffraction and ultraviolet absorption spectroscopy showed that the Zr: Dy: LiNbO3 crystal still maintained the original lattice structure of the pure lithium niobate crystal, and the doped ions entered the crystal by preferential substitution of Nb Li 4 + , and doped ions entered the crystal When Nb Li 4 + is completely replaced, ions are doped to replace the normal Nb and Li positions into the crystal. The lattice constant with the increase of Zr content shows a trend of first becoming larger and then smaller. Finally, the optical uniformity of Zr4+ doped concentration on Zr: Dy: LiNbO3 crystals was studied by birefringence gradient method. The results showed that with the increase of Zr4+ ion doping concentration, the crystal optical uniformity of Zr: Dy: LiNbO3 gradually increased, and the optical uniformity reached the highest when doped at a concentration of 4 mol%. Based on the Li-site vacancy model, the experimental results are discussed in detail.

Structural Formation and Properties of Eco-Friendly Foam Concrete Modified with Coal Dust

Foam concrete is a popular energy-efficient construction material with a fairly wide range of usage in buildings and structures. Increasing ecological efficiency and reducing construction costs by the application of different types of industrial waste in the manufacturing technology of this composite is a promising direction. The main goal of this study is to investigate the possibility of coal dust (CD) waste inclusion in the technology of energy-efficient cellular concrete produced by foam concrete technology. Test samples of foam concrete were made using coal dust by partially replacing cement in the range of 0–10% in increments of 2%. The following primary characteristics of foam concrete were studied: fluidity of mixtures; compressive strength; density; thermal conductivity of foam concrete. An X-ray diffraction analysis of foam concrete composites was performed, which showed changes in their phase composition when using coal dust as a modifier. Coal dust in rational quantities from 2% to 6% improves the physical and mechanical characteristics of foam concrete and increases the structure uniformity. The optimal values of the foam concrete characteristics were recorded at a dosage of coal dust of 6%. At the same time, the density decreased by 2.3%, the compressive strength increased by 15.6%, and the thermal conductivity coefficient decreased by 8.9% compared to the ordinary composition. The use of the resulting foam concrete is advisable in enclosing structures to create high energy efficiency of buildings and structures due to the improved structure and properties.

ANALYSIS OF CELLULOSIC FIBER MORPHOLOGY INFLUENCES ON MASS DISTRIBUTION UNIFORMITY IN TISSUE PAPER THROUGH STATISTICAL GEOMETRY

"Quality attributes of tissue products establish important differentials in the current scenario of fierce competition. Although the formation of the tissue paper is not monitored in industrial processes, it is imperative to recognize its importance for developing quality properties. A theoretical analysis of influences of the fiber morphology and furnish composition on the prediction of mass distribution uniformity in the paper forming process is presented. The theory utilizes the Poisson distribution for the grammage probability of points on the sheet, taken as a random fibrous network. The simulations revealed that lower grammage coefficients of variation could be achieved with total or predominant addition of eucalyptus fibers in mixtures with Pinus spp. fibers. The results provide meaningful insights into the understanding of how the selection of fiber type and pulp blend could help in achieving suitable structural uniformity of the sheet, in the forming process, in view of the expected paper quality."

CMOS-Compatible Ultrathin Superconducting NbN Thin Films Deposited by Reactive Ion Sputtering on 300 mm Si Wafer

We report a milestone in achieving large-scale, ultrathin (~5 nm) superconducting NbN thin films on 300 mm Si wafers using a high-volume manufacturing (HVM) industrial physical vapor deposition (PVD) system. The NbN thin films possess remarkable structural uniformity and consistently high superconducting quality across the entire 300 mm Si wafer, by incorporating an AlN buffer layer. High-resolution X-ray diffraction and transmission electron microscopy analyses unveiled enhanced crystallinity of (111)-oriented δ-phase NbN with the AlN buffer layer. Notably, NbN films deposited on AlN-buffered Si substrates exhibited a significantly elevated superconducting critical temperature (~2 K higher for the 10 nm NbN) and a higher upper critical magnetic field or Hc2 (34.06 T boost in Hc2 for the 50 nm NbN) in comparison with those without AlN. These findings present a promising pathway for the integration of quantum-grade superconducting NbN films with the existing 300 mm CMOS Si platform for quantum information applications.

Developing rapid electrochemical relithiation protocols for scalable relithiation of lithium-ion battery cathode materials

The recent and ongoing boom in electric vehicle sales has caused the circularity of the supply chain for electric vehicle battery materials to come under a great deal of scrutiny. Innovative recycling processes, or direct recycling, that offer the possibility of reducing the cost of recycling are one possible solution to regaining resources from end-of-life (EoL) electric vehicle batteries. Electrochemically shuttling lithium back into the cathode, or electrochemical relithiation, is a possible technique for restoring lithium content to NMC materials (EoL) in a direct recycling process. This study provides essential understanding towards developing an electrochemical relithiation protocol that will restore lithium loss in intercalation cathode materials that reach EoL by loss of lithium inventory (LLI) as opposed to other degradation mechanisms like loss of active material (LAM), cation mixing or phase transition. Electrochemically aged NMC cathode materials have been prepared and characterized to establish the extent of EoL material structural degradation and lithium loss. A model-informed experimental process is used to identify the optimal electrochemical relithiation protocol to minimize the time taken to relithiate EoL materials and maximize the amount of lithium restored. Protocols were evaluated based on their ability to enable rapid lithium intercalation, maintain structural uniformity in the EoL material and fully restore lithium content. An optimal protocol was identified at elevated temperatures utilizing a novel scanning voltage step.