Multicomponent Interface Research Articles

Reversible Li-ion trade-off in ultrathick sulfur cathodes for practical lean Li–S batteries

The use of low electrolyte volume is beneficial to improve energy density but severely limits access over obscured sulfur, along with sluggish ion kinetics and aggravated polarization, as the ion imbalance across the multicomponent interface of thick sulfur cathodes at a lean electrolyte viciously dominates the sulfur electrokinetics. Herein, we demonstrate that an ion imbalance at the interfaces of a thick electrode with a lean electrolyte can be compensated by the ion trade-off strategy utilizing a cationic ion conductive active binder. It ensures sustained lithium-ion donation/release over the vicinity of slow electrolyte percolation to realize an ion-enriched sulfur–binder–electrolyte interface. The in-situ evolved ionic interface essentially activates the inaccessible sulfur, bringing about additional capacity and low ion and charge transfer resistances. The active binder adopts sulfur cathodes housing 8.1 mg cm–2 with an E/S ratio of 6 µL mg–1 electrochemically utilized 60.89 % sulfur, corresponding to a 1020 mAh g–1 capacity. The lean Li–S pouch cell delivers an energy density of 324 Wh kg–1, demonstrating the efficacy of ion trade-off to ease the interfacial barrier. This study would open up a new paradigm in potentially designing thick electrodes for multiple high energy density batteries.

Multicomponent Interface and Electronic Structure Engineering in Ir-Doped CoMO4-Co(OH)2 (M = W and Mo) Enable Promoted Oxygen Evolution Reaction.

The core principles of multicomponent interface and electronic structure engineering are essential in designing high-performance catalysts for the oxygen evolution reaction (OER). However, combining these aspects within a catalyst is a significant challenge. In this investigation, a novel approach involving the development of hybrid Ir-doped CoMO4-Co(OH)2 (M = W and Mo) hollow nanoboxes was introduced, enabling remarkably efficient water oxidation electrocatalysis. Constructed from ultrathin nanosheet-assembled hollow nanoboxes, these structures boast a wealth of active centers for intermediate species, which in turn enhance both charge transfer and mass transport capabilities. Moreover, the compelling electronic and synergistic effects arising from the interaction between CoMO4 and Co(OH)2 significantly bolster OER electrocatalysis by facilitating efficient electron transfer. The introduction of Ir atoms serves to strategically adjust the electronic structure, fine-tune its electronic state, and operate as active centers to enhance OER electrocatalysis, thus diminishing the overpotential. This configuration results in Ir-CoWO4-Co(OH)2 and Ir-CoMoO4-Co(OH)2 exhibiting impressively low overpotentials of 252 and 261 mV, respectively, to 10 mA cm-2. Utilized in conjunction with the Pt/C catalyst in a two-electrode system for overall water splitting, a mere 1.53 V cell potential is needed to achieve the desired 10 mA cm-2 current density.

Strong interface interaction enriched surface Co3+ cations on Co3O4-LaCoO3 composite catalyst for highly efficient toluene oxidation

Interface interaction existed in the multicomponent determines the catalytic performance of composite catalysts. Herein, a Co3O4-LaCoO3 (Co-La) composite catalyst with strong spinel-perovskite interface interaction was successfully synthesized via a one-pot sol-gel method for the catalytic oxidation of toluene. The activity test results showed that the optimal 1Co3O4–4LaCoO3 (1Co-4La) catalyst exhibits much higher catalytic activity (T90 = 215 °C, GHSV = 50,000 h−1) than Co3O4 (T90 = 295 °C), LaCoO3 (T90 = 256 °C) and 1Co3O4/4LaCoO3 (1Co/4La) (prepared by mechanical ball-milling, T90 = 285 °C). Characterizations revealed that the strong spinel-perovskite interface interaction generated between the Co3O4 spinel and LaCoO3 perovskite in 1Co-4La facilitates the transfer of interfacial electrons, contributing to the exposure of surface active Co3+ and the enhanced oxidation ability of surface active Co3+ on 1Co-4La. In addition, the reactive lattice oxygen of surface Co3+–O on 1Co-4La effectively promotes the decomposition of toluene into CO2, enabling the low-temperature oxidation of toluene through the Mars-van Krevelen (MvK) mechanism. This work provides insight into the promotional effect of multicomponent interface interaction on enhancing catalytic performance of spinel-perovskite composite catalysts.

Microwave non-thermal fusion of MOFs derived Cu-O-Ce interface for boosting CO preferential oxidation

Engineering of uniformly-distributed and well-combined multi-component interface is sustainable but challenging for acquiring heterogeneous catalysts. Herein, the low energy consumption of microwave-fuse preparation is imposed on metal-organic frameworks (MOFs) namely Cu-MOF and Ce-MOF to manipulate Cu-O-Ce interface for preferential CO oxidation in H2-rich stream. By comprehensive characterizations, it is discovered that a unique spontaneous-migration of active Cu species onto Ce matrix will be driven by the microwave-fuse to form evenly-distributed and compactly-integrated Cu-O-Ce interface at low temperature, which is 200 °C lower than that required by traditional pyrolysis, clearly indicating the unique non-thermal function of microwave processing on fine-tuning oxide composite interface. In-situ Raman and in-situ DRIFTs further elucidate the improvement on synergistic redox feature along Cu2+-Ovac-Ce3+, leading to 100 % conversion of CO at 75–170 °C. These findings suggest that the unique self-migration of active metal species driven by non-thermal microwave-fuse is worthy of noting as an applicable strategy to acquire efficient multi-component solid interface for advanced heterogeneous catalysis as well as the current system for preferential CO oxidation in H2.

Bandwidth Limitation of Directly Contacted Graphene–Silicon Optoelectronics

Electrically contacting layered materials on a complementary metal-oxide-semiconductor transistor (CMOS)-processed lateral silicon homojunction offers a new platform enabling postfabrication-free high-speed hybrid optoelectronic devices on chip. Understanding detailed junction formation and radiofrequency (RF) response on the multicomponent interface between directly contacted silicon nanophotonic devices and low-bandgap materials is essential for predicting the performance of those active components. Electrostatic carrier distribution as well as the dynamics of externally injected carriers are strongly influenced by spatially varying Schottky barriers on the vertical heterojunctions. In this work, we analyze the high-speed RF response of a graphene “bonded” lateral silicon p-i-n junction. The multijunction structure on the hybrid structure is parametrized by fitting a small-signal model to the broadband coherent radio frequency response of the hybrid device at a series of different carrier injection rate...

Plasmolysis-Inspired Nanoengineering of Functional Yolk-Shell Microspheres with Magnetic Core and Mesoporous Silica Shell.

Yolk-shell nanomaterials with a rattle-like structure have been considered ideal carriers and nanoreactors. Traditional methods to constructing yolk-shell nanostructures mainly rely on multistep sacrificial template strategy. In this study, a facile and effective plasmolysis-inspired nanoengineering strategy is developed to controllably fabricate yolk-shell magnetic mesoporous silica microspheres via the swelling-shrinkage of resorcinol-formaldehyde (RF) upon soaking in or removal of n-hexane. Using Fe3O4@RF microspheres as seeds, surfactant-silica mesostructured composite is deposited on the swelled seeds through the multicomponent interface coassembly, followed by solvent extraction to remove surfactant and simultaneously induce shrinkage of RF shell. The obtained yolk-shell microspheres (Fe3O4@RF@void@mSiO2) possess a high magnetization of 40.3 emu/g, high surface area (439 m2/g), radially aligned mesopores (5.4 nm) in the outer shell, tunable middle hollow space (472-638 nm in diameter), and a superparamagnetic core. This simple method allows a simultaneous encapsulation of Au nanoparticles into the hollow space during synthesis, and it leads to spherical Fe3O4@RF@void-Au@mSiO2 magnetic nanocatalysts, which show excellent catalysis efficiency for hydrogenation of 4-nitrophenol by NaBH4 with a high conversion rate (98%) and magnetic recycling stability.

A decomposition-based uncertainty quantification approach for environmental impacts of aviation technology and operation

AbstractAs a measure to manage the climate impact of aviation, significant enhancements to aviation technologies and operations are necessary. When assessing these enhancements and their respective impacts on the climate, it is important that we also quantify the associated uncertainties. This is important to support an effective decision and policymaking process. However, such quantification of uncertainty is challenging, especially in a complex system that comprises multiple interacting components. The uncertainty quantification task can quickly become computationally intractable and cumbersome for one individual or group to manage. Recognizing the challenge of quantifying uncertainty in multicomponent systems, we utilize a divide-and-conquer approach, inspired by the decomposition-based approaches used in multidisciplinary analysis and optimization. Specifically, we perform uncertainty analysis and global sensitivity analysis of our multicomponent aviation system in a decomposition-based manner. In this work, we demonstrate how to handle a high-dimensional multicomponent interface using sensitivity-based dimension reduction and a novel importance sampling method. Our results demonstrate that the decomposition-based uncertainty quantification approach can effectively quantify the uncertainty of a feed-forward multicomponent system for which the component models are housed in different locations and owned by different groups.

An Interface Coassembly in Biliquid Phase: Toward Core-Shell Magnetic Mesoporous Silica Microspheres with Tunable Pore Size.

Core-shell magnetic mesoporous silica microspheres (Magn-MSMs) with tunable large mesopores in the shell are highly desired in biocatalysis, magnetic bioseparation, and enrichment. In this study, a shearing assisted interface coassembly in n-hexane/water biliquid systems is developed to synthesize uniform Magn-MSMs with magnetic core and mesoporous silica shell for an efficient size-selective biocatalysis. The synthesis features the rational control over the electrostatic interaction among cationic surfactant molecules, silicate oligomers, and Fe3O4@RF microspheres (RF: resorcinol formaldehyde) in the presence of shearing-regulated solubilization of n-hexane in surfactant micelles. Through this multicomponent interface coassembly, surfactant-silica mesostructured composite has been uniformly deposited on the Fe3O4@RF microspheres, and core-shell Magn-MSMs are obtained after removing the surfactant and n-hexane. The obtained Magn-MSMs possess excellent water dispersibility, uniform diameter (600 nm), large and tunable perpendicular mesopores (5.0-9.0 nm), high surface area (498-623 m(2)/g), large pore volume (0.91-0.98 cm(3)/g), and high magnetization (34.5-37.1 emu/g). By utilization of their large and open mesopores, Magn-MSMs with a pore size of about 9.0 nm have been demonstrated to be able to immobilize a large bioenzyme (trypsin with size of 4.0 nm) with a high loading capacity of ∼97 μg/mg via chemically binding. Magn-MSMs with immobilized trypsin exhibit an excellent convenient and size selective enzymolysis of low molecular proteins in the mixture of proteins of different sizes and a good recycling performance by using the magnetic separability of the microspheres.

Micropatterning: Site‐Specific Differentiation of Neural Stem Cell Regulated by Micropatterned Multicomponent Interfaces (Adv. Healthcare Mater. 2/2014)

Micropatterning: Site‐Specific Differentiation of Neural Stem Cell Regulated by Micropatterned Multicomponent Interfaces (Adv. Healthcare Mater. 2/2014)

Site‐Specific Differentiation of Neural Stem Cell Regulated by Micropatterned Multicomponent Interfaces

Stem cell microenvironments are enriched by signals from a variety of components, which cooperate spatially and temporally to regulate cellular function. In vitro recapitulating such complexity in a well-controlled manner is elusive. Here, a platform for patterning multiple bio-active proteins on a single substrate is developed and optimized, and is used it to study the cooperative involvement of cell-matrix interaction and cell-cell signaling in regulating neural stem cell (NSC) function. An affinity-capturing-based multi-step microcontact printing is used to pattern, extracellular matrix proteins, and cell-cell signaling ligands, as intersecting lines on a nonadhesive background. Such design provides spatial segregation of signals from different extrinsic components, while allowing cell traffic between them during their proliferation and differentiation processes. Rat embryonic neural stem cells are cultured and characterized on the multicomponent substrates patterned with different combinations of fibronectin, N-cadherin, and Jagged1 proteins and allow to proliferate and differentiate over long term. It is found that local presentation of Notch signaling ligand (Jagged1) or cell adhesion molecule (N-cadherin) effectively modulate the balance between cell-cell and cell-matrix interaction, and significantly change the overall spatial remodeling of NSC differentiation. This platform provides an unambiguous approach to study the spatial and temporal cooperative involvement of different extrinsic components in regulating stem cell behavior. It is also readily expandable for inclusion of extra components and applicable to use with other types of cells, which provide a powerful tool for basic study of cell-material interaction or advanced tissue-interface engineering.

Study of Interfacial Stiffness by Using the Structural Interface Model Based on Elastic Mechanics

The recently proposed structural interface model is a realistic model of thick interfaces, but the bars of the structure are assumed iso-stiffness. In the present work, the structural interface consisting of pairs of bars with different stiffness is developed. Based on the neutral inclusion concept and elastic mechanics, the stiffness of bars of the structural interface is studied. It is found that all the bars have the same stiffness in a special loading condition of equal-biaxial tension. The finite element simulations for glass fiber-reinforced epoxy composite reveal that the fiber does not alter the prescribed stress due to the presence of the structural interface. Compared with the iso-stiffness-bar interface, the developed structure interface is more suitable for characterizing a multi-component interface and more flexible to be designed.

Modeling Diluted Bitumen−Water Interfacial Compositions Using a Thermodynamic Approach

A two-layer interfacial model was proposed to describe the layout of large and small surface-active species on a diluted bitumen/water interface. Based on this model, large asphaltene species “float” on the interface, with only “point contacts” with the actual interface, allowing small surface-active species to occupy almost the entire interfacial area at the same time. This interfacial model is able to reconcile the contradiction found in the literature (i.e., the small average molar area inferred from the interfacial tension data and the dominance of large asphaltene species on the interface, detected through chemical analyses). The multicomponent interface was further quantitatively modeled, using a modified Butler-type equation. The resulting parameters are consistent with many experimental findings in the literature.

The Adsorption of Unsymmetrical Spiroalkanedithiols onto Gold Affords Multi-Component Interfaces that Are Homogeneously Mixed at the Molecular Level

Exposure of the unsymmetrical spiroalkanedithiol, 2-octyl-2-pentadecylpropane-1,3-dithiol, to the surface of gold afforded a multicomponent self-assembled monolayer (SAM) in which the differing tail groups were well mixed at the molecular level. The new “mixed” SAM was characterized by ellipsometry, contact angle goniometry, polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS), and atomic force microscopy (AFM). Comparison of the new SAM to those generated by the coadsorption of mixtures of normal alkanethiols having analogous chain lengths and surface compositions showed that local domain formation (or “islanding”) of the tail groups found in the latter SAMs was absent in the SAM derived from the unsymmetrical spiroalkanedithiol.