Construction of 1D Molecular Conductive Wires Through a Polarized Gene Weaving Strategy for Efficient Electromagnetic Wave Absorption.

The growing threat of electromagnetic pollution has become a pressing safety concern. Metal-organic framework (MOF) derivatives are considered ideal candidates for mitigating electromagnetic radiation. However, due to the limitations imposed by complex post-processing and disruption of pristine crystal structures, the mechanisms of electromagnetic wave absorption remain unclear, let alone achieving atomic-level regulation in MOF derivatives.

Topologically Tunable Conjugated Metal-Organic Frameworks for Modulating Conductivity and Chemiresistive Properties for NH Sensing.

Electrically conductive metal-organic frameworks (cMOFs) have garnered significant attention in materials science due to their potential applications in modern electrical devices. However, achieving effective modulation of their conductivity has proven to be a major challenge. In this study, we have successfully prepared cMOFs with high conductivity by incorporating electron-donating fused thiophen rings in the frameworks and extending their π-conjugated systems through ring-closing reactions.

Adjusting the Stacking Model of Two-Dimensional Covalent Organic Frameworks for Volatile Acid Sensing via Spatial Effects.

Covalent organic frameworks (COFs) are polymer networks with a precise structure and permanent porosity, making them an attractive platform for the detection of volatile analytes due to their chemical stability and accessible active sites. In this study, based on electron-rich -tetrakis(4-aminophenyl)-1,4-benzenediamine moiety, two 2D COFs with different topological structures and stacking models were designed by the strategy of spatial effect. The conductivity of the AB-stacked COF-NUST-20 was an order of magnitude higher than that of the AA-stacked COF-NUST-30.

Three-dimensional covalent organic frameworks based on a π-conjugated tetrahedral node.

The construction of three-dimensional (3D) covalent organic frameworks (COFs), especially fully conjugated 3D COFs, is a long-standing challenge. Herein, we report a saddle-like, π-conjugated cyclooctatetrathiophene (COTh) as a tetrahedral node to construct fully conjugated 3D COFs. The present work enriches the structural diversities and potential applications of 3D COFs.

Synthesis of All Thiophene-Based [7]Helicenes and Trithienothiepines with Isomeric Location of Sulfur Atoms Based on Intramolecular Selectivity of Deprotonation.

Three unsymmetric thiophene-based [7]helicenes, namely, --, --, and --, with different isomeric locations of sulfur atoms in two terminal thiophene rings were efficiently synthesized using dithieno[2,3-:3',2'-]thiophene (-), dithieno[2,3-:2',3'-]thiophene (-), and dithieno[2,3-:3',4'-]thiophene (-) as building blocks via Suzuki cross-coupling and intramolecular cyclization reactions. Aside from these racemic [7]helicenes, two novel heterocyclic isomers, namely, trithienothiepines and , were simultaneously obtained during the intramolecular cyclization. Two novel deprotonations of bi-s and cyclization for synthesizing target compounds showed high selectivity and efficiently constructed both s and s.

Highly Robust Non-Noble Alkaline Hydrogen-Evolving Electrocatalyst from Se-Doped Molybdenum Disulfide Particles on Interwoven CoSe Nanowire Arrays.

Developing efficient non-noble and earth-abundant hydrogen-evolving electrocatalysts is highly desirable for improving the energy efficiency of water splitting in base. Molybdenum disulfide (MoS ) is a promising candidate, but its catalytic activity is kinetically retarded in alkaline media due to the unfavorable water adsorption and dissociation feature. A heterogeneous electrocatalyst is reported that is constructed by selenium-doped MoS (Se-MoS ) particles on 3D interwoven cobalt diselenide (CoSe ) nanowire arrays that drives the hydrogen evolution reaction (HER) with fast reaction kinetics in base.

Theoretical investigations on the unsymmetrical effect of β-link Zn-porphyrin sensitizers on the performance for dye-sensitized solar cells.

Dye sensitizers play an important role in dye-sensitized solar cells (DSSCs). As a promising strategy for the design of novel porphyrin sensitizers, the asymmetric modification of the porphyrin ring to meso-link porphyrin sensitizer has emerged in recent years, which can improve the light-harvesting properties and enhance the electron distribution. In this work, in order to reveal the essence of the effect of unsymmetrical substitution on the performance of β-link porphyrin dyes in DSSCs, four kinds of common β-link porphyrin dyes with different structures are calculated by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT).

Effective Augmentation of Complex Networks.

Networks science plays an enormous role in many aspects of modern society from distributing electrical power across nations to spreading information and social networking amongst global populations. While modern networks constantly change in size, few studies have sought methods for the difficult task of optimising this growth. Here we study theoretical requirements for augmenting networks by adding source or sink nodes, without requiring additional driver-nodes to accommodate the change i.

Molecular dynamics simulation of melting and crystallization processes of polyethylene clusters confined in armchair single-walled carbon nanotubes.

The confined interaction is important to understand the melting and crystallization of polymers within single-wall carbon tube (SWNT). However, it is difficult for us to observe this interaction. In the current work, the structures and behaviors of melting and crystallization for polyethylene (PE) clusters confined in armchair single-walled carbon nanotubes ((n,n)-SWNTs) are investigated and examined based on molecular dynamics (MD) simulations.

Some Insight into Stability of Amorphous Poly(ethylene glycol) Dimethyl Ether Polymers Based on Molecular Dynamics Simulations.

Poly(ethylene glycol) dimethyl ether (PEGDME) polymers are widely used as drug solid dispersion reagents. They can cause the amorphization of drugs and improve their solubility, stability, and bioavailability. However, the mechanism about why amorphous PEGDME 2000 polymer is highly stable is unclear so far.