Robust Nuclear Spin Polarization via Ground-State Level Anticrossing of Boron Vacancy Defects in Hexagonal Boron Nitride.

Nuclear spin polarization plays a crucial role in quantum information processing and quantum sensing. In this work, we demonstrate a robust and efficient method for nuclear spin polarization with boron vacancy (V_{B}^{-}) defects in hexagonal boron nitride (h-BN) using ground-state level anticrossing (GSLAC). We show that GSLAC-assisted nuclear polarization can be achieved with significantly lower laser power than excited-state level anticrossing, making the process experimentally more viable.

Wiring Covalent Organic Frameworks with Conducting Polymers.

Covalent organic frameworks are a class of crystalline porous polymers formed by linking organic units into periodically aligned skeletons and pores. Here we report a strategy for wiring these frameworks with conducting polymers via wall engineering and polymerization. We anchored each edge site with one pyrrole unit, which is densely packed along the z direction yet protruded from pore walls.

[4]Rhombene: Solution-Phase Synthesis and Application in Distributed Feedback Lasers With Emission Beyond 830 nm.

Graphene-like molecules with multiple zigzag edges are emerging as promising gain materials for organic lasers. Their emission wavelengths can vary widely, ranging from visible to near-infrared (NIR), as the molecular size increases. Specifically, rhombus-shaped molecular graphenes with two pairs of parallel zigzag edges, known as [n]rhombenes, are excellent candidates for NIR lasers due to their small energy gaps.

Interfacial Engineering of Ag/C Catalysts for Practical Electrochemical CO Reduction to CO.

Electrochemical CO reduction to value-added chemicals by renewable energy sources is a promising way to implement the artificial carbon cycle. During the reaction, especially at high current densities for practical applications, the complex interaction between the key intermediates and the active sites would affect the selectivity, while the reconfiguration of electrocatalysts could restrict the stability. This paper describes the fabrication of Ag/C catalysts with a well-engineered interfacial structure, in which Ag nanoparticles are partially encapsulated by C supports.

Visible Light-Induced Radical Cascade Difluoromethylation/Cyclization of Unactivated Alkenes: Access to CFH-Substituted Polycyclic Imidazoles.

An efficient and mild protocol for the visible light-induced radical cascade difluoromethylation/cyclization of imidazoles with unactivated alkenes using easily accessible and bench-stable difluoromethyltriphenylphosphonium bromide as the precursor of the -CFH group has been developed to afford CFH-substituted polycyclic imidazoles in moderate to good yields. This strategy, along with the construction of Csp-CFH/C-C bonds, is distinguished by mild conditions, no requirement of additives, simple operation, and wide substrate scope. In addition, the mechanistic experiments have indicated that the difluoromethyl radical pathway is essential for the methodology.

Tailor-Made Heterocharged Covalent Organic Framework Membrane for Efficient Ion Separation.

Pore size sieving, Donnan exclusion, and their combined effects seriously affect ion separation of membrane processes. However, traditional polymer-based membranes face some challenges in precisely controlling both charge distribution and pore size on the membrane surface, which hinders the ion separation performance, such as heavy metal ion removal. Herein, the heterocharged covalent organic framework (COF) membrane is reported by assembling two kinds of ionic COF nanosheets with opposite charges and different pore sizes.

Fluorescent Enhancement of [AgS] Microplates by Mechanical Force Induced Crystallinity Breaking.

Mechanofluorochromic materials are a type of "smart" material because of their adjustable fluorescent properties under external mechanical force, making them significant members of the materials family. However, as the fluorescent characteristics of these materials highly depend on their microstructures, the still insufficiently in-depth research linking molecular structures to light emission motivates researchers to explore the fluorescent properties of these materials under external stimuli. In this work, based on synthetic [AgS] microplates, we explore a fascinating mechanical-induced photoluminescent enhancement phenomenon.

Chiral multiferroicity in two-dimensional hybrid organic-inorganic perovskites.

Chiral multiferroics offer remarkable capabilities for controlling quantum devices at multiple levels. However, these materials are rare due to the competing requirements of long-range orders and strict symmetry constraints. In this study, we present experimental evidence that the coexistence of ferroelectric, magnetic orders, and crystallographic chirality is achievable in hybrid organic-inorganic perovskites [(R/S)-β-methylphenethylamine]CuCl.

Engineering catalytic defects via molecular imprinting for high energy Li-S pouch cells.

Heterogeneous catalysis promises to accelerate sulfur-involved conversion reactions in lithium-sulfur batteries. Solid-state LiS dissociation remains as the rate-limiting step because of the weakly matched solid-solid electrocatalysis interfaces. We propose an electrochemically molecular-imprinting strategy to have a metal sulfide (MS) catalyst with imprinted defects in positions from which the pre-implanted LiS has been electrochemically removed.

Improving both performance and stability of n-type organic semiconductors by vitamin C.

Organic semiconductors (OSCs) are one of the most promising candidates for flexible, wearable and large-area electronics. However, the development of n-type OSCs has been severely held back due to the poor stability of their most candidates, that is, the intrinsically high reactivity of negatively charged polarons to oxygen and water. Here we demonstrate a general strategy based on vitamin C to stabilize n-type OSCs, remarkably improving the performance and stability of their device, for example, organic field-effect transistors.

Enhanced Oxygen Accumulation for a Hydrophobic Cathode in Lean-Oxygen Seawater Batteries.

The unsatisfactory oxygen reduction reaction (ORR) kinetics caused by the inherent lean-oxygen marine environment brings low power density for metal-dissolved oxygen seawater batteries (SWBs). In this study, we propose a seawater/electrode interfacial engineering strategy by constructing a hydrophobic coating to realize enhanced mass transfer of dissolved oxygen for the fully immersed cathode of SWBs. Accumulation of dissolved oxygen from seawater to the catalyst is particularly beneficial for improving the ORR performance under lean-oxygen conditions.

Photorefinery of Biomass and Plastics to Renewable Chemicals using Heterogeneous Catalysts.

The photocatalytic conversion of biomass and plastic waste provides opportunities for sustainable fuel and chemical production. Heterogeneous photocatalysts, typically composed of semiconductors with distinctive redox properties in their conduction band (CB) and valence band (VB), facilitate both the oxidative and reductive valorization of organic feedstocks. This article provides a comprehensive overview of recent advancements in the photorefinery of biomass and plastics from the perspective of the redox properties of photocatalysts.

Deciphering and Integrating Functionalized Side Chains for High Ion-Conductive Elastic Ternary Copolymer Solid-State Electrolytes for Safe Lithium Metal Batteries.

A critical challenge in solid polymer lithium batteries is developing a polymer matrix that can harmonize ionic transportation, electrochemical stability, and mechanical durability. We introduce a novel polymer matrix design by deciphering the structure-function relationships of polymer side chains. Leveraging the molecular orbital-polarity-spatial freedom design strategy, a high ion-conductive hyperelastic ternary copolymer electrolyte (CPE) is synthesized, incorporating three functionalized side chains of poly-2,2,2-Trifluoroethyl acrylate (PTFEA), poly(vinylene carbonate) (PVC), and polyethylene glycol monomethyl ether acrylate (PEGMEA).

Origin of copper as a unique catalyst for C-C coupling in electrocatalytic CO reduction.

High yields of C products through electrocatalytic CO reduction (eCOR) can only be obtained using Cu-based catalysts. Here, we adopt the generalized frontier molecular orbital (MO) theory based on first-principles calculations to identify the origin of this unique property of Cu. We use the grand canonical ensemble (or fixed potential) approach to ensure that the calculated Fermi level, which serves as the frontier orbital of the metal catalyst, accurately represents the applied electrode potentials.

Experimental observation of exceptional bound states in a classical circuit network.

Exceptional bound (EB) states represent a unique new class of robust bound states protected by the defectiveness of non-Hermitian exceptional points. Conceptually distinct from the more well-known topological states and non-Hermitian skin states, they were recently discovered as a novel source of negative entanglement entropy in the quantum entanglement context. Yet, EB states have been physically elusive, being originally interpreted as negative probability eigenstates of the propagator of non-Hermitian Fermi gases.

Dual-targeted fluorescent probe for tracking polarity and phase transition processes during lipophagy.

Eukaryotic cells regulate various cellular processes through membrane-bound and membrane-less organelles, enabling active signal communication and material exchange. Lysosomes and lipid droplets are representative organelles, contributing to cell lipophagy when their interaction and metabolism are disrupted. Our limited understanding of the interacting behaviours and physicochemical properties of different organelles during lipophagy hinders accurate diagnosis and treatment of related diseases.

Electrostatic Repulsion Facilitated Ion Transport in Covalent-Organic Framework Membranes.

Covalent-organic framework (COF) membranes are increasingly used for many potential applications including ion separation, fuel cells, and ion batteries. It is of central importance to fundamentally and quantitatively understand ion transport in COF membranes. In this study, a series of COF membranes is designed with different densities and arrangements of functional groups and subsequently utilize molecular simulation to provide microscopic insights into ion transport in these membranes.

Highly-Polarized Solar-Blind Ultraviolet Organic Photodetectors.

Developing high-performance polarization-sensitive ultraviolet photodetectors is crucial for their application in military remote sensing, detection, bio-inspired navigation, and machine vision. However, the significant absorption in the visible light range severely limits the application of polarization-sensitive ultraviolet photodetectors, such as high-quality anti-interference imaging. Here, based on a wide-bandgap organic semiconductor single crystal (trans-1,2-bis(5-phenyldithieno[2,3-b:3',2'-d]thiophen-2-yl)ethene, BPTTE), high-performance polarization-sensitive solar-blind ultraviolet photodetectors with a dichroic ratio close to 4.

Atomically dispersed MoNi alloy catalyst for partial oxidation of methane.

The catalytic partial oxidation of methane (POM) presents a promising technology for synthesizing syngas. However, it faces severe over-oxidation over catalyst surface. Attempts to modify metal surfaces by incorporating a secondary metal towards C-H bond activation of CH with moderate O* adsorption have remained the subject of intense research yet challenging.

Large-Language-Model-Based AI Agent for Organic Semiconductor Device Research.

Large language models (LLMs) have attracted widespread attention recently, however, their application in specialized scientific fields still requires deep adaptation. Here, an artificial intelligence (AI) agent for organic field-effect transistors (OFETs) is designed by integrating the generative pre-trained transformer 4 (GPT-4) model with well-trained machine learning (ML) algorithms. It can efficiently extract the experimental parameters of OFETs from scientific literature and reshape them into a structured database, achieving precision and recall rates both exceeding 92%.

Tuning Electrode Work Function and Surface Energy for Solution Shearing High-Performance Organic Field-Effect Transistors.

A bottom-contact organic field-effect transistor (OFET) is easily adaptable to the standard lithography process because the contact electrodes are deposited before the organic semiconductor (OSC). However, the low surface energy of bare electrodes limits utilizing solution-processed single-crystal OSCs. Additionally, the bare electrode usually leads to a significant charge injection barrier, owing to its relatively low work function (WF).

Solution-Processed Ultralow Voltage Organic Transistors With Sharp Switching for Adaptive Visual Perception.

Neuromorphic visual systems can emulate biological retinal systems to perceive visual information under different levels of illumination, making them have considerable potential for future intelligent vehicles and vision automation. However, the complex circuits and high operating voltages of conventional artificial vision systems present great challenges for device integration and power consumption. Here, bioinspired synaptic transistors based on organic single crystal phototransistors are reported, which exhibit excitation and inhibition synaptic plasticity with time-varying.