Isomerism Effect of 3D Dimeric Acceptors for Non-halogenated Solvent-Processed Organic Solar Cells with 20% Efficiency.

Organic photovoltaic materials that can be processed via non-halogenated solvents are crucial for the large-area manufacturing of organic solar cells (OSCs). However, the limited available of electron acceptors with adequate solubility and favorable molecular packing presents a challenge in achieving efficient non-halogenated solvent-processed OSCs. Herein, inspired by the three-dimensional dimeric acceptor CH8-4, we employed a molecular isomerization strategy to synthesize its isomers, CH8-4A and CH8-4B, by tuning the position of fluorine (F) atom in the central unit.

Reversal of chirality in solutions and aggregates of chiral tetrachlorinated diperylene diimides towards efficient circularly polarized light detection.

Helicenes exhibit promise as active layer materials for circularly polarized light (CPL) detectors due to their strong chiroptical activity. However, their practical application is limited by the complicated synthesis and loosely solid-state packing. This study introduces a chiral induction strategy towards the synthesis of helicene derivatives, chiral tetrachlorinated diperylene diimides (()-4CldiPDI or ()-4CldiPDI).

Chiral Metal-Free Anti-Perovskite with Strong Chiroptical Nonlinearity.

The nonlinear chiroptical properties of chiral metal halide perovskite has attracted substantial attention in recent years. In order to overcome the inherent limitations of metal halide, such as high costs, potential toxicity, challenges with recycling, especially the limited laser-induced damage threshold (LDT), we have successfully constructed the first chiral metal-free anti-perovskite, with the aim of utilizing it in second harmonic generation-circular dichroism (SHG-CD). Moreover, the anti-perovskite composed entirely of small organic ions typically display a more extensive transparent window, which could contribute a high LDT.

Rebuilding Peripheral F, Cl, Br Footprints on Acceptors Enables Binary Organic Photovoltaic Efficiency Exceeding 19.7 .

Given homomorphic fluorine (F), chlorine (Cl) and bromine (Br) atoms are featured with gradually enlarged polarizability/atomic radius but decreased electronegativity, the rational screen of halogen species and locations on small molecular acceptors (SMAs) is quite essential for acquiring desirable molecular packing to boost efficiency of organic solar cells (OSCs). Herein, three isomeric SMAs (CH-F, CH-C and CH-B) are constructed by delicately rebuilding peripheral F, Cl, Br footprints on both central and end units. Such a re-permutation of peripheral halogens could not only maintain the structural symmetry of SMAs to the maximum, but also acquire extra asymmetric benefits of enhanced dipole moment and intramolecular charge transfer, etc.

Linker Group Fluorination Boosts Photovoltaic Performance of Branch-Connected Dimerized Acceptors.

Branch-connected dimerized acceptors can take full advantages of four end units in enhancing molecular packing comparing to that of terminal-connected ones, thus potentially reaching the best balance between stability and power conversion efficiency (PCE) of organic solar cells (OSCs). Herein, two branch-connected dimerized acceptors, namely D1 and D2, are developed by employing bithiophene and difluorinated bithiophene as linker groups, respectively. Induced by the fluorine atoms on linker group, D2 affords a larger molar extinction coefficient, more importantly, the optimized nanoscale film morphology and superior charge transport behavior comparing to D1.

Enhancing Circularly Polarized Luminescence Dissymmetry Factor of Chiral Cylindrical Molecules to -0.56 through Intramolecular Short-Range Charge Transfer.

High-performance circularly polarized luminescent (CPL) materials have received wide attention recently by virtue of broad application in circularly polarized light-emitting diodes, 3D display, and encryption. Reaching both high luminescence efficiency and strong luminescence dissymmetry factor () is still a challenging goal that requires continuous efforts. Herein, we performed a systematic theoretical investigation on the chiroptical properties of helical cylindrical molecules (-)-[4]cyclo-2,6-anthracene [(-)-[4]CA] and ()-[4]cyclo-2,8-chrysenylene [()-[4]CC], and found that the unique and symmetric cylindrical structure could make the transition dipole moment components offset along the cylindrical surface but concentrated along the vertical central axis.

Delicate Regulation of Central Substituents Boosts Organic Photovoltaic Performance of Dimeric Acceptors.

Dimeric acceptors are expected to satisfy both excellent power conversion efficiency (PCE) and operational stability of organic solar cells (OSCs). However, comparing to highly planar and symmetrical monomer-like acceptors, the quite different steric/spatial configurations of dimeric acceptors affect device outcomes greatly. Herein, on basis of the same dimeric molecular platform that constructed by bridging central units of two monomer-like acceptor, diverse substituents (─OCH for D1, ─CH for D2, and ─CF for D3) are grafted on central units to regulate the three dimensions (3D) geometries of dimeric acceptors delicately.

Asymmetrified Benzothiadiazole-Based Solid Additives Enable All-Polymer Solar Cells with Efficiency Over 19 .

Disordered polymer chain entanglements within all-polymer blends limit the formation of optimal donor-acceptor phase separation. Therefore, developing effective methods to regulate morphology evolution is crucial for achieving optimal morphological features in all-polymer organic solar cells (APSCs). In this study, two isomers, 4,5-difluorobenzo-c-1,2,5-thiadiazole (SF-1) and 5,6-difluorobenzo-c-1,2,5-thiadiazole (SF-2), were designed as solid additives based on the widely-used electron-deficient benzothiadiazole unit in nonfullerene acceptors.

Extending the π-Conjugation of a Donor-Acceptor Covalent Organic Framework for High-Rate and High-Capacity Lithium-Ion Batteries.

Realizing high-rate and high-capacity features of Lihium-organic batteries is essential for their practical use but remains a big challenge, which is due to the instrinsic poor conductivity, limited redox kinetics and low utility of organic electrode mateials. This work presents a well-designed donor-acceptor Covalent Organic Framework (COFs) with extended conjugation, mesoscale porosity, and dual redox-active centers to promote fast charge transfer and multi-electron processes. As anticipated, the prepared cathode with benzo [1,2-b:3,4-b':5,6-b''] trithiophene (BTT) as p-type and pyrene-4,5,9,10-tetraone (PTO) as n-type material (BTT-PTO-COF) delivers impressive specific capacity (218 mAh g at 0.

Design of health information management model for elderly care using an advanced higher-order hybrid clustering algorithm from the perspective of sports and medicine integration.

In the context of integrating sports and medicine domains, the urgent resolution of elderly health supervision requires effective data clustering algorithms. This paper introduces a novel higher-order hybrid clustering algorithm that combines density values and the particle swarm optimization (PSO) algorithm. Initially, the traditional PSO algorithm is enhanced by integrating the Global Evolution Dynamic Model (GEDM) into the Distribution Estimation Algorithm (EDA), constructing a weighted covariance matrix-based GEDM.

2D Conjugated Polymer Thin Films for Organic Electronics: Opportunities and Challenges.

2D conjugated polymers (2DCPs) possess extended in-plane π-conjugated lattice and out-of-plane π-π stacking, which results in enhanced electronic performance and potentially unique band structures. These properties, along with predesignability, well-defined channels, easy postmodification, and order structure attract extensive attention from material science to organic electronics. In this review, the recent advance in the interfacial synthesis and conductivity tuning strategies of 2DCP thin films, as well as their application in organic electronics is summarized.

Galvanic-Replacement-Assisted Synthesis of Nanostructured Silver-Surface for SERS Characterization of Two-Dimensional Polymers.

Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful technology in trace analysis. However, the wide applications of SERS in practice are limited by the expensive substrate materials and the complicated preparation processes. Here we report a simple and economical galvanic-replacement-assisted synthesis route to prepare Ag nanoparticles on Cu(0) foil (nanoAg@Cu), which can be directly used as SERS substrate.

Two-Dimensional Conjugated Polymers: a New Choice For Organic Thin-Film Transistors.

Organic thin-film transistors (OTFTs) as a vital component among transistors have shown great potential in smart sensing, flexible displays, and bionics due to their flexibility, biocompatibility and customizable chemical structures. Even though linear conjugated polymer semiconductors are common for constructing channel materials of OTFTs, advanced materials with high charge carrier mobility, tunable band structure, robust stability, and clear structure-property relationship are indispensable for propelling the evolution of OTFTs. Two-dimensional conjugated polymers (2DCPs), featured with conjugated lattice, tailorable skeletons, and functional porous structures, match aforementioned criteria closely.

ErF microcrystals controllably deposited in perfluoride glass for upconversion red emission.

To the best of our knowledge, this paper first reports ErF microcrystals controllably deposited in perfluoride glass using phase-separation engineering techniques. The sample exhibited strong upconversion red-light emission owing to the small distance between Er ions and low phonon energy (585 cm). The sample has a high red/green ratio of up to 18.

Multiple strategies of improving photocatalytic water splitting efficiency in 2D arsenic sesquichalcogenides.

Improving the solar-to-hydrogen efficiency has always been a significant topic in the field of photocatalysis. Based on first-principles calculations, herein, we propose multiple strategies to improve the photocatalytic properties of 2D arsenic sesquichalcogenides for full water splitting. The new configurations AsSTe and AsSeTe monolayers, derived from the AsTe monolayers by surface modification, are manifested to be typical infrared-light driven photocatalysts.

Dual transmission channels at metal-MoS/WSe hetero-bilayer interfaces.

van der Waals heterostructures (vdWHs) open the possibility of creating novel semiconductor materials at the atomic scale that demonstrate totally new physics and enable unique functionalities, and have therefore attracted great interest in the fields of advanced electronic and optoelectronic devices. However, the interactions between metals and vdWHs semiconductors require further investigation as they directly affect or limit the advancement of high-performance electronic devices. Here we study the contact behavior of MoS/WSe vdWHs in contact with a series of bulk metals using electronic structure calculations and quantum transport simulations.

Effects of Inorganic Substitutions and Different Metal Electrode Materials on Electronic Transport Properties of Organic Molecular Devices.

Incorporating inorganic components into organic molecular devices offers one novel alternative to address challenges existing in the fabrication and integration of nanoscale devices. In this study, using a theoretical method of density functional theory combined with the nonequilibrium Green's function, a series of benzene-based molecules with group III and V substitutions, including borazine molecule and XBNH (X = Al or Ga, = 1-3) molecules/clusters, are constructed and investigated. An analysis of electronic structures reveals that the introduction of inorganic components effectively reduces the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, albeit at the cost of reduced aromaticity in these molecules/clusters.

Porcine reproductive and respiratory syndrome virus degrades DDX10 via SQSTM1/p62-dependent selective autophagy to antagonize its antiviral activity.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a typical immunosuppressive virus devastating the global swine industry. DEAD-box helicases (DDXs) are a family of ATP-dependent RNA helicases that are predominantly implicated in modulating cellular RNA metabolism. Meanwhile, a growing number of studies have suggested that some DDXs are associated with innate immunity and virus infection, so they are considered potential antiviral targets.

Study on the Influencing Factors of Farmers' Adoption of Conservation Tillage Technology in Black Soil Region in China: A Logistic-ISM Model Approach.

The adoption of conservation tillage technology can improve the production efficiency of black soils (mollisols), and it has great significance to ensure the sustainable development of agriculture. This paper takes farmers in the black soil region of Jilin Province as the research object, uses 442 survey data of farmers in seven municipal areas in the black soil region of Jilin Province, constructs a logistic-ISM model, first determines the influencing factors of farmers' adoption of conservation tillage technology, and then analyzes the hierarchical structure of each influencing factor. The results show that: (1) among the eight significant influencing factors of farmers' adoption of conservation tillage technology, age, whether they know the government's subsidies for conservation tillage and the number of labor force are the deep-rooted factors; (2) Education level, whether you know that the government is promoting conservation tillage, and the planting area are intermediate level factors; (3) whether they have received the technical services of conservation tillage and whether the cultivated land is scattered is the direct factors.

Tunable Dirac states in doped BS monolayers.

Two-dimensional (2D) Dirac materials have been a research hotspot due to their intriguing properties, such as high carrier mobility and ballistic charge transport. Here, we demonstrate that the BS monolayer with a hexagonal structure, which has been reported as a photocatalyst, can be tuned to new 2D Dirac materials by doping atoms. The Young's modulus can reach 65.

Strain-tunable electronic structure and anisotropic transport properties in Janus MoSSe and g-SiC van der Waals heterostructure.

The van der Waals heterostructures (vdWHs) create a multi-purpose platform to design unique structures for efficient photovoltaic and optoelectronic applications. In this study, on the basis of the first-principles calculations, we present a type-II semiconducting MoSSe/g-SiC vdWH with a moderate bandgap value of 1.31 eV.

Imaging of electron transition and bond breaking in the photodissociation of H via ultrafast X-ray photoelectron diffraction.

We theoretically investigate the photodissociation dynamics of H2+ using the methodology of ultrafast X-ray photoelectron diffraction (UXPD). We use a femtosecond infrared pulse to prompt a coherent excitation from the molecular vibrational state (v = 9) of the electronic ground state (1sσ) and then adopt another time-delayed attosecond X-ray pulse to probe the dynamical properties. We have calculated photoionization momentum distributions by solving the non-Born-Oppenheimer time-dependent Schrödinger equation (TDSE).

Novel 2D BSas a metal-free photocatalyst for water splitting.

Metal-free semiconductors with desirable characteristics have recently gained great attention in the field of hydrogen generation. The non-metal material BShas two phases, hexagonal BS(-BS) and orthorhombic BS(-BS), which compose a novel class of 2D materials. Both-BSand-BSmonolayers are direct semiconductors with bandgaps of 2.