Overcoming Electrostatic Interaction via Pulsed Electroreduction for Boosting the Electrocatalytic Urea Synthesis.

Electrocatalytic urea synthesis under ambient conditions offers a promising alternative strategy to the traditional energy-intensive urea industry protocol. Limited by the electrostatic interaction, the reduction reaction of anions at the cathode in the electrocatalytic system is not easily achievable. Here, we propose a novel strategy to overcome electrostatic interaction via pulsed electroreduction.

The long non-coding RNA BDNF-AS induces neuronal cell apoptosis by targeting miR-125b-5p in Alzheimer's disease models.

Background: At least 55 million individuals suffer from dementia globally, of which Alzheimer's disease (AD) accounts for 60-70% of cases. Alzheimer's disease is the only major cause of death that is still growing. However, the molecular mechanisms are largely unknown in the progress of AD.

Constructing an ultrastable imidazole covalent organic framework for concurrent uranium detection and recovery.

Uranium is one of the most important strategic resources for the development of the nuclear industry, but its unintended release has created potential environmental and health risks. It is highly desired to explore new methods that enable concurrent uranium monitoring and recovery for environmental protection and sustainable development of the nuclear industry. Here, for the first time, an imidazole fluorescent covalent organic framework (named PyTT-Tp) with ultrastable skeleton and open nanopore channel is synthesized by condensing ammonium acetate, 1,3,5-triformylphloroglucinol and pyrene-4,5,9,10-tetrone.

High-Sensitivity Sensing in All-Dielectric Metasurface Driven by Quasi-Bound States in the Continuum.

Quasi-bound states in the continuum (quasi-BIC) in all-dielectric metasurfaces provide a crucial platform for sensing due to its ability to enhance strong matter interactions between light-waves and analytes. In this study, a novel high-sensitivity all-dielectric sensor composed of a periodic array of silicon (Si) plates with square nanoholes in the continuous near-infrared band is theoretically proposed. By adjusting the position of the square nanohole, the symmetry-protected BIC and Friedrich-Wintgen BIC (FW-BIC) can be excited.

Olefin-linked cationic covalent organic frameworks for efficient extraction of ReO/TcO.

Efficient extraction of radioactive TcO from strong acid/base solutions by porous adsorbents is extremely desirable but remains a great challenge. To overcome the challenge, here we report the first example of an olefin-linked cationic covalent organic framework (COF) named BDBI-TMT with excellent acid, base and radiation stability is synthesized by integrating robust imidazolium salt-based linkers with triazine building blocks. BDBI-TMT shows an ultra-fast adsorption kinetics (equilibrium is reached within 1 min) and an excellent ReO (a non-radioactive surrogate of TcO) capture capacity of 726 mg g, which can be attributed to the abundance of precisely tailored imidazolium salt-based units on the highly accessible pore walls of the ordered pore channels.

Nano-crumples induced Sn-Bi bimetallic interface pattern with moderate electron bank for highly efficient CO electroreduction.

CO electroreduction reaction offers an attractive approach to global carbon neutrality. Industrial CO electrolysis towards formate requires stepped-up current densities, which is limited by the difficulty of precisely reconciling the competing intermediates (COOH* and HCOO*). Herein, nano-crumples induced Sn-Bi bimetallic interface-rich materials are in situ designed by tailored electrodeposition under CO electrolysis conditions, significantly expediting formate production.

Group Velocity Modulation and Light Field Focusing of the Edge States in Chirped Valley Graphene Plasmonic Metamaterials.

The valley degree of freedom, like the spin degree of freedom in spintronics, is regarded as a new information carrier, promoting the emerging valley photonics. Although there exist topologically protected valley edge states which are immune to optical backscattering caused by defects and sharp edges at the inverse valley Hall phase interfaces composed of ordinary optical dielectric materials, the dispersion and the frequency range of the edge states cannot be tuned once the geometrical parameters of the materials are determined. In this paper, we propose a chirped valley graphene plasmonic metamaterial waveguide composed of the valley graphene plasmonic metamaterials (VGPMs) with regularly varying chemical potentials while keeping the geometrical parameters constant.

Chiral graphene plasmonic Archimedes' spiral nanostructure with tunable circular dichroism and enhanced sensing performance.

Circular dichroism spectroscopy is frequently used to characterize the chiral biomolecules by measuring the absorption spectra contrast between the left-handed circularly polarized light and the right-handed circularly polarized light. Compared with biomolecules, chiral metal plasmonic nanostructures also produce a strong circular dichroism response in the range of near-infrared. However, due to the large damping rate, the non-adjustable resonant frequency of the conventional metals, the applications of chiral metal plasmonic nanostructures in the fields of photoelectric detection and chemical and biochemical sensing are restricted.

"Fast" Plasmons Propagating in Graphene Plasmonic Waveguides with Negative Index Metamaterial Claddings.

We propose the monolayer graphene plasmonic waveguide (MGPW), which is composed of graphene core sandwiched by two graphene metamaterial (GMM) claddings and investigate the properties of plasmonic modes propagating in the waveguide. The effective refraction index of the GMMs claddings takes negative (or positive) at the vicinity of the Dirac-like point in the band structure. We show that when the effective refraction index of the GMMs is positive, the plasmons travel forward in the MGPW with a positive group velocity (vg > 0, vp > 0).

Amorphous/Crystalline Hetero-Phase TiO -Coated α-Fe O Core-Shell Nanospindles: A High-Performance Artificial Nitrogen Fixation Electrocatalyst.

Electrochemical nitrogen fixation techniques have emerged as a promisingly sustainable approach to face the challenge associated with nitrogen activation of ammonia synthesis by the Haber-Bosch process under ambient conditions. Herein, the performance of electrocatalytic nitrogen reduction for the production of α-Fe O nanospindles coated with mesoporous TiO with different crystallinity [denoted as α-Fe O @mTiO -X (X=300, 400, and 500 °C)] were investigated. The as-prepared α-Fe O @mTiO -400 composite exhibits a large NH yield (27.

Mo-Doped FeP Nanospheres for Artificial Nitrogen Fixation.

Electrochemical conversion of N to NH under ambient conditions is a promising and environmentally friendly route compared with the CO-emitting and energy-intensive Haber-Bosch process. Nevertheless, due to ultrahigh stability of N, it is urgent to explore efficient catalysts to weaken and activate the N≡N bond. Here, we report the Mo-doped iron phosphide (Mo-FeP) nanosphere as a valid transition-metal-based catalyst for electrochemical N-to-NH fixation under ambient conditions.

Multiple Fano Resonances with Tunable Electromagnetic Properties in Graphene Plasmonic Metamolecules.

Multiple Fano resonances (FRs) can be produced by destroying the symmetry of structure or adding additional nanoparticles without changing the spatial symmetry, which has been proved in noble metal structures. However, due to the disadvantages of low modulation depth, large damping rate, and broadband spectral responses, many resonance applications are limited. In this research paper, we propose a graphene plasmonic metamolecule (PMM) by adding an additional 12 nanodiscs around a graphene heptamer, where two Fano resonance modes with different wavelengths are observed in the extinction spectrum.

BC nanosheets decorated with in situ-derived boron-doped graphene quantum dots for high-efficiency ambient N fixation.

In situ-derived boron-doped graphene quantum dots can significantly improve the activity of boron carbide nanosheets for artificial N2 fixation and reduction with superior electrocatalytic activity (NH3 yield: 28.6 μg h-1 mgcat.-1 at -0.

Potential contribution of microRNA-125b targeting p38MAPK to relieving intermittent hypoxia-induced dementia of rat models.

Allowing for the correlation between intermittent hypoxia and impaired cognition, we intended to figure out whether and how dementia-relevant biomolecules (e.g. miR-125b and p38MAPK) might participate in weakening of intelligence in the context of intermittent hypoxia.

WITHDRAWN: MicroRNA-125b can Target p38MAPK to Resolve Intermittent Hypoxia- Induced Dementia in Murine Models.

The article entitled, “MicroRNA-125b can Target p38MAPK to Resolve Intermittent Hypoxia-Induced Dementia in Murine Models” submitted in Current Neurovascular Research (CNR) by Dr. Xu Chen has been withdrawn from the journal in accordance with BSP Editorial Policies.

A flexible control on electromagnetic behaviors of graphene oligomer by tuning chemical potential.

In this work, we demonstrate that the electromagnetic properties of graphene oligomer can be drastically modified by locally modifications of the chemical potentials. The chemical potential variations of different positions in graphene oligomer have different impacts on both extinction spectra and electromagnetic fields. The flexible tailoring of the localizations of the electromagnetic fields can be achieved by precisely adjusting the chemical potentials of the graphene nanodisks at corresponding positions.

High-performance artificial nitrogen fixation at ambient conditions using a metal-free electrocatalyst.

Conversion of naturally abundant nitrogen to ammonia is a key (bio)chemical process to sustain life and represents a major challenge in chemistry and biology. Electrochemical reduction is emerging as a sustainable strategy for artificial nitrogen fixation at ambient conditions by tackling the hydrogen- and energy-intensive operations of the Haber-Bosch process. However, it is severely challenged by nitrogen activation and requires efficient catalysts for the nitrogen reduction reaction.

Dynamic tailoring of electromagnetic behaviors of graphene plasmonic oligomers by local chemical potential.

In the mid-infrared and terahertz (THz) regime, graphene supports tunable surface plasmon resonance (SPR) by controlling the chemical potential, which promotes light-matter interaction at the selected wavelength, showing exceptional promise for optoelectronic applications. In this article, we show that the electromagnetic (EM) response of graphene oligomers can be substantially modified by the modification of the local chemical potential, strengthening or reducing the intrinsic plasmonic modes. The effect mechanism is corroborated by a graphene nanocluster composed of 13 nanodisks with D6h symmetry; by transforming to D3h symmetry, the effect mechanism was retained and more available plasmonic resonance modes appeared.

Pseudospin Dependent One-Way Transmission in Graphene-Based Topological Plasmonic Crystals.

Originating from the investigation of condensed matter states, the concept of quantum Hall effect and quantum spin Hall effect (QSHE) has recently been expanded to other field of physics and engineering, e.g., photonics and phononics, giving rise to strikingly unconventional edge modes immune to scattering.

Iodide-derived nanostructured silver promotes selective and efficient carbon dioxide conversion into carbon monoxide.

It is of great importance to design and develop highly active and selective electrocatalysts for the CO reduction reaction (CORR). In this communication, we report an iodide-derived nanostructured silver catalyst (ID-Ag) as an excellent CORR catalyst that is able to electrochemically reduce CO to CO with approximately 94.5% selectivity at the potential of -0.

Topologically protected edge states in graphene plasmonic crystals.

A two-dimensional graphene plasmonic crystal composed of periodically arranged graphene nanodisks is proposed. We show that the band topology effect due to inversion symmetry broken in the proposed plasmonic crystals is obtained by tuning the chemical potential of graphene nanodisks. Utilizing this kind of plasmonic crystal, we constructed N-shaped channels and realized topologically edged transmission within the band gap.

Investigation of beam splitter in a zero-refractive-index photonic crystal at the frequency of Dirac-like point.

The Dirac-like cone dispersion of the photonic crystal induced by the three-fold accidental degeneracy at the Brillouin center is calculated in this paper. Such photonic crystals can be mapped to zero-refractive-index materials at the vicinity of the Dirac-like point frequency, and utilized to construct beam splitter of high transmission efficiency. The splitting ratio is studied as a function of the position of the input/output waveguides.

Optimization of the Fano Resonance Lineshape Based on Graphene Plasmonic Hexamer in Mid-Infrared Frequencies.

In this article, the lineshape of Fano-like resonance of graphene plasmonic oligomers is investigated as a function of the parameters of the nanostructures, such as disk size, chemical potential and electron momentum relaxation time in mid-infrared frequencies. Also, the mechanism of the optimization is discussed. Furthermore, the environmental index sensing effect of the proposed structure is revealed, and a figure of merit of 25.

Dynamically Tunable Plasmon-Induced Transparency in On-chip Graphene-Based Asymmetrical Nanocavity-Coupled Waveguide System.

A graphene-based on-chip plasmonic nanostructure composed of a plasmonic bus waveguide side-coupled with a U-shaped and a rectangular nanocavities has been proposed and modeled by using the finite element method in this paper. The dynamic tunability of the plasmon-induced transparency (PIT) windows has been investigated. The results reveal that the PIT effects can be tuned via modifying the chemical potential of the nanocavities and plasmonic bus waveguide or by varying the geometrical parameters including the location and width of the rectangular nanocavity.

Electromagnetic field coupling characteristics in graphene plasmonic oligomers: from isolated to collective modes.

In this paper, we propose a plasmonic tetramer composed of coupled graphene nanodisks. The transformation from the isolated to the collective modes of the proposed structure is investigated by analysing the whispering-gallery modes and extinction spectra with various inter-nanodisk gap distances. In addition, the effect of introducing a central nanodisk into the tetramer on the extinction spectra is explored, which leads to Fano resonance.