3D Covalent Organic Frameworks with 16-Connectivity for Photocatalytic C(sp)-C(sp) Cross-Coupling.

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology.

In situ Construction of Single-Atom Electronic Bridge on COF to Enhance Photocatalytic H Production.

Photocatalytic hydrogen production is one of the most valuable technologies in the future energy system. Here, we designed a metal-covalent organic frameworks (MCOFs) with both small-sized metal clusters and nitrogen-rich ligands, named COF-CuTG. Based on our design, small-sized metal clusters were selected to increase the density of active sites and shorten the distance of electron transport to active sites.

Insight into the Mechanism of CO Chemical Fixation into Epoxides by Windmill-Shaped Polyoxovanadate and -BuNX (X = Br, I).

Carbon dioxide (CO) coupled with epoxide to generate cyclic carbonate stands out in carbon neutrality due to its 100% atom utilization. In this work, the mechanism of CO cycloaddition with propylene oxide (PO) cocatalyzed by windmill-shaped polyoxovanadate, [(CNH)(CHO)VVO]·4CHOH (V-1), and -BuNX (X = Br, I) was thoroughly investigated using density functional theory (DFT) calculations. The ring-opening, CO-insertion, and ring-closing steps of the process were extensively studied.

Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis.

Covalent-organic frameworks (COFs) with photoinduced donor-acceptor (D-A) radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining [6 + 4] nodes to construct -type 3D COFs, first reported in COF chemistry.

A solvent-free processed low-temperature tolerant adhesive.

Ultra-low temperature resistant adhesive is highly desired yet scarce for material adhesion for the potential usage in Arctic/Antarctic or outer space exploration. Here we develop a solvent-free processed low-temperature tolerant adhesive with excellent adhesion strength and organic solvent stability, wide tolerable temperature range (i.e.

Floquet engineering of the orbital Hall effect and valleytronics in two-dimensional topological magnets.

We show that circularly polarized light is a versatile way to manipulate both the orbital Hall effect and band topology in two-dimensional ferromagnets. Employing the hexagonal lattice, we proposed that interactions between light and matter allow for the modulation of the valley polarization effect, and then band inversions, accompanied by the band gap closing and reopening processes, can be achieved subsequently at two valleys. Remarkably, the distribution of orbital angular momentum can be controlled by the band inversions, leading to the Floquet engineering of the orbital Hall effect, as well as the topological phase transition from a second-order topological insulator to a Chern insulator with in-plane magnetization, and then to a normal insulator.

Coupled Electronic and Magnonic Topological States in Two-Dimensional Ferromagnets.

Magnetic materials offer a fertile playground for fundamental physics discovery, with not only electronic but also magnonic topological states intensively explored. However, one natural material with both electronic and magnonic nontrivial topologies is still unknown. Here, we demonstrate the coexistence of first-order topological magnon insulators (TMIs) and electronic second-order topological insulators (SOTIs) in 2D honeycomb ferromagnets, giving rise to the nontrivial corner states being connected by the charge-free magnonic edge states.

Topology-Engineered Orbital Hall Effect in Two-Dimensional Ferromagnets.

Recent advances in the manipulation of the orbital angular momentum (OAM) within the paradigm of orbitronics presents a promising avenue for the design of future electronic devices. In this context, the recently observed orbital Hall effect (OHE) occupies a special place. Here, focusing on both the second-order topological and quantum anomalous Hall insulators in two-dimensional ferromagnets, we demonstrate that topological phase transitions present an efficient and straightforward way to engineer the OHE, where the OAM distribution can be controlled by the nature of the band inversion.

Coordinate-wise monotonic transformations enable privacy-preserving age estimation with 3D face point cloud.

The human face is a valuable biomarker of aging, but the collection and use of its image raise significant privacy concerns. Here we present an approach for facial data masking that preserves age-related features using coordinate-wise monotonic transformations. We first develop a deep learning model that estimates age directly from non-registered face point clouds with high accuracy and generalizability.

Screening TLR4 Binding Peptide from Venom Glands Based on Phage Display.

Toll-like receptor 4 (TLR4) is a crucial inflammatory signaling pathway that can serve as a potential treatment target for various disorders. A number of inhibitors have been developed for the TLR4 pathway, and although no inhibitors have been approved for clinical use, most have been screened against the TLR4-MD2 conformation. The venom gland is the organ of venomous snakes that secretes substances that are toxic to other animals.

Layer-coupled corner states in two-dimensional topological multiferroics.

The structural diversity and controllability in two-dimensional (2D) materials offers an intriguing platform for exploring a wide range of topological phenomena. The layer degree of freedom, as a novel technique for material manipulation, requires further investigation regarding its association with topological states. Here, using first-principles calculations and a tight-binding model, we propose a novel mechanism that couples the second-order topological corner states with the layer degree of freedom.

Bridging the Homogeneous and Heterogeneous Catalysis by Supramolecular Metal-Organic Cages with Varied Packing Modes.

Integrating the advantages of homogeneous and heterogeneous catalysis has proved to be an optimal strategy for developing catalytic systems with high efficiency, selectivity, and recoverability. Supramolecular metal-organic cages (MOCs), assembled by the coordination of metal ions with organic linkers into discrete molecules, have performed solvent processability due to their tunable packing modes, endowing them with the potential to act as homogeneous or heterogeneous catalysts in different solvent systems. Here, the design and synthesis of a series of stable {Cu} cluster-based tetrahedral MOCs with varied packing structures are reported.

Photocatalytic aerobic oxidation of C(sp)-H bonds.

In modern industries, the aerobic oxidation of C(sp)-H bonds to achieve the value-added conversion of hydrocarbons requires high temperatures and pressures, which significantly increases energy consumption and capital investment. The development of a light-driven strategy, even under natural sunlight and ambient air, is therefore of great significance. Here we develop a series of hetero-motif molecular junction photocatalysts containing two bifunctional motifs.

Engineering Gapless Edge States from Antiferromagnetic Chern Homobilayer.

We put forward that stacked Chern insulators with opposite chiralities offer a strategy to achieve gapless helical edge states in two dimensions. We employ the square lattice as an example and elucidate that the gapless chiral and helical edge states emerge in the monolayer and antiferromagnetically stacked bilayer, characterized by Chern number and spin Chern number , respectively. Particularly, for a topological phase transition to the normal insulator in the stacked bilayer, a band gap closing and reopening procedure takes place accompanied by helical edge states disappearing, where the Chern insulating phase in the monolayer vanishes at the same time.

Calix[4]arene-Functionalized Titanium-Oxo Compounds for Perceiving Differences in Catalytic Reactivity Between Mono- and Multimetallic Sites.

While the difference in catalytic reactivity between mono- and multimetallic sites is often attributed to more than just the number of active sites, still few catalyst model systems have been developed to explore more underlying causal factors. In this work, we have elaborately designed and constructed three stable calix[4]arene (C4A)-functionalized titanium-oxo compounds, , , and , with well-defined crystal structures, increasing nuclearity, and tunable light absorption capacity and energy levels. Among them, and can be taken as model catalysts to compare the differences in reactivity between mono- and multimetallic sites.

Additive-free selective oxidation of aromatic alcohols with molecular oxygen catalyzed by a mixed-valence polyoxovanadate-based metal-organic framework.

Selective oxidation of alcohols to aldehydes is an industrially significant chemical transformation. Herein, we report a mixed-valence polyoxovanadate-based metal-organic framework (MOF), (Hbix){[Cd(bix)][VIV8VV7OCl]}·3HO (V-Cd-MOF), for catalyzing the additive-free oxidation of a series of aromatic alcohols with high selectivity and in nearly quantitative yield to the corresponding aldehydes with O as the oxidant. Experimental results, corroborated with density functional theory calculations, indicate that it is the synergistic operation of the dual active sites of the V-O-V building units in the polyoxovanadate cluster that is responsible for the excellent catalytic performance observed: on the one hand, the exposed and readily accessible reduced V site is believed to activate O, resulting in a reactive oxygen species for the subsequent activation and breaking of the substrate's C-H bond.

Magnetic Weyl Semimetal in BaCrSe with Long-Distance Distribution of Weyl Points.

Weyl semimetals (WSMs) have attracted great attentions that provide intriguing platforms for exploring fundamental physical phenomena and future topotronics applications. Despite the fact that numerous WSMs are achieved, WSMs with long-distance distribution of Weyl points (WPs) in given material candidates remain elusive. Here, the emergence of intrinsic ferromagnetic WSMs in BaCrSe with the nontrivial nature explicitly confirmed by the Chern number and Fermi arc surface states analysis is theoretically demonstrated.

Theoretical Mechanistic Study of C(sp )-C(sp ) Cross-Coupling by Photoredox-Mediated Iridium(III)/Nickel(II)/Quinuclidine Triple Catalysis.

The photoredox-mediated iridium(III)/nickel(II)/3-acetoxyquinuclidine triple-synergistic catalysis was comprehensively investigated by taking a C(sp )-C(sp ) bond cross-coupling as a reaction model using density functional theory (DFT) calculations. The synergistic mechanism of the triple catalytic system includes a reductive quenching cycle (Ir -*Ir -Ir -Ir ), an organocatalytic cycle, and a nickel catalytic cycle (Ni -Ni -Ni -[Ni ] -Ni ). Electronic process analysis shows that 3-acetoxyquinuclidine acts as a hydrogen atom transfer (HAT) catalyst to regioselectively provide α-carbon centered radical.

Engineering Second-Order Corner States in 2D Multiferroics.

The understanding and manipulate of the second-order corner states are central to both fundamental physics and future topotronics applications. Despite the fact that numerous second-order topological insulators (SOTIs) are achieved, the efficient engineering in a given material remains elusive. Here, the emergence of 2D multiferroics SOTIs in SbAs and BP monolayers is theoretically demonstrated, and an efficient and straightforward way for engineering the nontrivial corner states by ferroelasticity and ferroelectricity is remarkably proposed.

Robust Second-Order Topological Insulators with Giant Valley Polarization in Two-Dimensional Honeycomb Ferromagnets.

Magnetic topological states have attracted great attention that provide exciting platforms for exploring prominent physical phenomena and applications of topological spintronics. Here, using a tight-binding model and first-principles calculations, we put forward that, in contrast to previously reported magnetic second-order topological insulators (SOTIs), robust SOTIs can emerge in two-dimensional ferromagnets regardless of magnetization directions. Remarkably, we identify intrinsic ferromagnetic 2H-RuCl and Janus VSSe monolayers as experimentally feasible candidates of predicted robust SOTIs with the emergence of nontrivial corner states along different magnetization directions.

Molecular oxidation-reduction junctions for artificial photosynthetic overall reaction.

Constructing redox semiconductor heterojunction photocatalysts is the most effective and important means to complete the artificial photosynthetic overall reaction (i.e., coupling CO photoreduction and water photo-oxidation reactions).