HexagonRingCalculator: A Handy Code for Hexagonal Ring Characterization in Atomistic Simulations.

Hexagonal rings are critical to the properties of many nanomaterials by determining their mechanical strength, thermal stability, and electrical conductivity, therefore this kind of structure has been intensively concerned in computational studies. However, existing molecular dynamics (MD) simulation tools lack specialized functions for identifying and characterizing them. To address this gap, we developed HexagonRingCalculator, a tool for identifying hexagonal rings and calculating their geometric properties, including bond lengths, ring area, and circularity, directly from MD simulation data.

New Engineering Science Insights into the Electrode Materials Pairing of Electrochemical Energy Storage Devices.

Pairing the positive and negative electrodes with their individual dynamic characteristics at a realistic cell level is essential to the practical optimal design of electrochemical energy storage devices. However, the complex relationship between the performance data measured for individual electrodes and the two-electrode cells used in practice often makes an optimal pairing experimentally challenging. Taking advantage of the developed tunable graphene-based electrodes with controllable structure, experiments with machine learning are successfully united to generate a large pool of capacitance data for graphene-based electrode materials with varied slit pore sizes, thicknesses, and charging rates and numerically pair them into different combinations for two-electrode cells.

Surface-Enriched Room-Temperature Liquid Bismuth for Catalytic CO Reduction.

Bismuth-based electrocatalysts are effective for carbon dioxide (CO) reduction to formate. However, at room temperature, these materials are only available in solid state, which inevitably suffers from surface deactivation, declining current densities, and Faradaic efficiencies. Here, the formation of a liquid bismuth catalyst on the liquid gallium surface at ambient conditions is shown as its exceptional performance in the electrochemical reduction of CO (i.

Unlocking Direct Lithium Extraction in Harsh Conditions through Thiol-Functionalized Metal-Organic Framework Subnanofluidic Membranes.

Metal-organic framework (MOF) membranes with high ion selectivity are highly desirable for direct lithium-ion (Li) separation from industrial brines. However, very few MOF membranes can efficiently separate Li from brines of high Mg/Li concentration ratios and keep stable in ultrahigh Mg-concentrated brines. This work reports a type of MOF-channel membranes (MOFCMs) by growing UiO-66-(SH) into the nanochannels of polymer substrates to improve the efficiency of MOF membranes for challenging Li extraction.

Unravelling the atomistic mechanisms underpinning the morphological evolution of Al-alloyed hematite.

Hydrothermal synthesis based upon the use of Al as the dopant and/or ethanol as the solvent is effective in promoting the growth of hematite into nanoplates rich in the (001) surface, which is highly active for a broad range of catalytic applications. However, the underpinning mechanism for the flattening of hematite crystals is still poorly comprehended. To close this knowledge gap, in this work, we have attempted intensive computational modelling to construct a binary phase diagram for FeO-AlO under typical hydrothermal conditions, as well as to quantify the surface energy of hematite crystal upon coverage with Al and ethanol molecules.

Assessment of Self-report, Palpation, and Surface Electromyography Dataset During Isometric Muscle Contraction.

Measuring muscle fatigue involves assessing various components within the motor system. While subjective and sensor-based measures have been proposed, a comprehensive comparison of these assessment measures is currently lacking. This study aims to bridge this gap by utilizing three commonly used measures: participant self-reported perceived muscle fatigue scores, a sports physiotherapist's manual palpation-based muscle tightness scores, and surface electromyography sensors.

Out-of-plane pressure and electron doping inducing phase and magnetic transitions in GeC/CrS/GeC van der Waals heterostructure.

Out-of-plane pressure and electron doping can affect interlayer interactions in van der Waals materials, modifying their crystal structure and physical and chemical properties. In this study, we used magnetic monolayer 1T/1T'-CrS and high symmetry 2D-honeycomb material GeC to construct a GeC/CrS/GeC triple layered van der Waals heterostructure (vdWH). Based on density functional theory calculations, we found that applying out-of-plane strain and doping with electrons could induce a 1T'-to-1T phase transition and consequently the ferromagnetic (FM)-to-antiferromagnetic (AFM) transition in the CrS layer.

A Preliminary Usability Study of Integrated Electronic Tattoo Surface Electromyography (sEMG) Sensors.

Surface electromyography (sEMG) sensor measures the user's muscle activities by noninvasively placing electrodes on the surface of the user's skin. It has been widely used in monitoring various human movements. Recently a wearable and flexible epidermal sensor system called Electronic Tattoo (E-Tattoo) has been developed to enable intimate attachment of electrodes on the skin, improving long-term comfort.

High-performance van der Waals antiferroelectric CuCrPS-based memristors.

Layered thio- and seleno-phosphate ferroelectrics, such as CuInPS, are promising building blocks for next-generation nonvolatile memory devices. However, because of the low Curie point, the CuInPS-based memory devices suffer from poor thermal stability (<42 °C). Here, exploiting the electric field-driven phase transition in the rarely studied antiferroelectric CuCrPS crystals, we develop a nonvolatile memristor showing a sizable resistive-switching ratio of ~ 1000, high switching endurance up to 20,000 cycles, low cycle-to-cycle variation, and robust thermal stability up to 120 °C.

Dynamic topological domain walls driven by lithium intercalation in graphene.

Stacking engineering in van der Waals (vdW) materials is a powerful method to control topological electronic phases for quantum device applications. Atomic intercalation into the vdW material can modulate the stacking structure at the atomic scale without a highly technical protocol. Here we report that lithium intercalation in a topologically structured graphene/buffer system on SiC(0001) drives dynamic topological domain wall (TDW) motions associated with stacking order change by using an in situ aberration-corrected low-energy electron microscope in combination with theoretical modelling.

Dehydration-enhanced ion-pore interactions dominate anion transport and selectivity in nanochannels.

State-of-the-art ion-selective membranes with ultrahigh precision are of significance for water desalination and energy conservation, but their development is limited by the lack of understanding of the mechanisms of ion transport at the subnanometer scale. Herein, we investigate transport of three typical anions (F, Cl, and Br) under confinement using in situ liquid time-of-flight secondary ion mass spectrometry in combination with transition-state theory. The operando analysis reveals that dehydration and related ion-pore interactions govern anion-selective transport.

Nitrogen rejection in natural gas using NaZSM-25 zeolite.

Natural gas reservoirs usually contain considerable amounts of nitrogen (N). Methane (CH) as the main component in natural gas must be purified before transferring to the pipeline or storing as liquified natural gas (LNG). Currently, energy-intensive cryogenic distillation is the only industrial approach for N rejection in natural gas.

Ion-Specific Nanoconfinement Effect in Multilayered Graphene Membranes: A Combined Nuclear Magnetic Resonance and Computational Study.

Ion adsorption within nanopores is involved in numerous applications. However, a comprehensive understanding of the fundamental relationship between in-pore ion concentration and pore size, particularly in the sub-2 nm range, is scarce. This study investigates the ion-species-dependent concentration in multilayered graphene membranes (MGMs) with tunable nanoslit sizes (0.

Writing-Speed Dependent Thresholds of Ferroelectric Domain Switching in Monolayer α-In Se.

An electrical-biased or mechanical-loaded scanning probe written on the ferroelectric surface can generate programmable domain nanopatterns for ultra-scaled and reconfigurable nanoscale electronics. Fabricating ferroelectric domain patterns by direct-writing as quickly as possible is highly desirable for high response rate devices. Using monolayer α-In Se ferroelectric with ≈1.

Size Limiting Elemental Ferroelectricity in Bi Nanoribbons: Observation, Mechanism, and Opportunity.

Combined with the inherent spin-orbital coupling effect, the elemental ferroelectricity of monolayer Bi (bismuthene) is the critical property that renders this system a 2D ferroelectric topological insulator. Here, using first-principles calculations, we systematically investigate the ferroelectric polarization in bismuthene nanoribbons and discover the width size limiting effect arising from the edge effects. The decreasing width led to the spontaneous transformation of the zigzag (ZZ) and armchair (AC) paired Bi nanoribbons into newly discovered high-symmetric nonpolarized nanoribbons.

Synergistic effect of nitrogen and oxygen dopants in 3D hierarchical porous carbon cathodes for ultra-fast zinc ion hybrid supercapacitors.

Zinc-ion hybrid supercapacitor is one of the most promising electrochemical energy storage devices for the applications needing both high energy densities and power densities. Nitrogen doping is an effective way to enhance the capacitive performance of porous carbon cathodes in zinc-ion hybrid supercapacitor. However, accurate evidence is yet needed to demonstrate how nitrogen dopants influence the charge storage of Zn and H cations.

Scalable high yield exfoliation for monolayer nanosheets.

Although two-dimensional (2D) materials have grown into an extended family that accommodates hundreds of members and have demonstrated promising advantages in many fields, their practical applications are still hindered by the lack of scalable high-yield production of monolayer products. Here, we show that scalable production of monolayer nanosheets can be achieved by a facile ball-milling exfoliation method with the assistance of viscous polyethyleneimine (PEI) liquid. As a demonstration, graphite is effectively exfoliated into graphene nanosheets, achieving a high monolayer percentage of 97.

Screening of Alkali Metal-Exchanged Zeolites for Nitrogen/Methane Separation.

Methane (CH) is the primary component of natural gas and must be purified to a certain level before it can be used as pipeline gas or liquified natural gas (LNG). In particular, nitrogen (N), a common contaminant in natural gas needs to be rejected to increase the heating value of the gas and meet the LNG product specifications. The development of energy-efficient N removal technologies is hampered by N's inertness and its resemblance to CH in terms of kinetic size and polarizability.

Silica-assisted pyro-hydrolysis of CaCl waste for the recovery of hydrochloric acid (HCl): Reaction pathways with the evolution of Ca(OH)Cl intermediate by experimental investigation and DFT modelling.

The chlorine evolution mechanism remains unclear during the thermal treatment of CaCl/Ca(OH)Cl-containing solid waste. In this paper, we have conducted both experimental investigation and density functional theory (DFT) calculation to elucidate the mechanism of pyro-hydrolysis of CaCl with and without SiO in the temperature ranges of 400-900 °C. It was determined that pyro-hydrolysis of CaCl alone generated a maximum of 12% HCl by decomposition into Ca(OH)Cl, which is a stable intermediate that can be reverted to CaCl at 800 °C.

Nitrogen Rejection from Methane via a "Trapdoor" K-ZSM-25 Zeolite.

Nitrogen (N) rejection from methane (CH) is the most challenging step in natural gas processing because of the close similarity of their physical-chemical properties. For decades, efforts to find a functioning material that can selectively discriminate N had little outcome. Here, we report a molecular trapdoor zeolite K-ZSM-25 that has the largest unit cell among all zeolites, with the ability to capture N in favor of CH with a selectivity as high as 34.

Can CO and Steam React in the Absence of Electrolysis at High Temperatures?

The fundamental question of whether CO can react with steam at high temperatures in the absence of electrolysis or high pressures is answered. These two gases are commonly co-present as industrial wastes. Herein, a simple experiment by flowing CO and steam through a CaCl matrix at 500-1000 °C and atmospheric pressure was designed.

Universal Approach to Fabricating Graphene-Supported Single-Atom Catalysts from Doped ZnO Solid Solutions.

Single-atom catalysts (SACs) have attracted widespread interest for many catalytic applications because of their distinguishing properties. However, general and scalable synthesis of efficient SACs remains significantly challenging, which limits their applications. Here we report an efficient and universal approach to fabricating a series of high-content metal atoms anchored into hollow nitrogen-doped graphene frameworks (M-N-Grs; M represents Fe, Co, Ni, Cu, etc.