Tuning the interlayer stacking of a vinylene-linked covalent organic framework for enhancing sacrificial agent-free hydrogen peroxide photoproduction.

The layer-stacking mode of a two-dimensional (2D) material plays a dominant role either in its topology or properties, but remains challenging to control. Herein, we developed alkali-metal ion-regulating synthetic control on the stacking structure of a vinylene-linked covalent triazine framework (termed spc-CTF) for improving hydrogen peroxide (HO) photoproduction. Upon the catalysis of EtONa in Knoevenagel polycondensation, a typical eclipsed stacking mode (spc-CTF-4@AA) was built, while a staggered one (spc-CTF-4@AB) was constructed using LiOH.

CCC pincer Ru complex-catalyzed C-H vinylation/6π-E-cyclization of aldimines for constructing 4-pyrido[1,2-]pyrimidines.

An unusual cascade C-H activation, vinylation and 6π-electrocyclization of 2-pyridyl aldimines with vinyl bromides/triflates was achieved using catalysis with a unique CCC pincer NHC-Ru(iii) complex (Cat B). This reaction was found to enable a rapid and diverse synthesis of polycyclic 4-pyrido[1,2-]pyrimidine derivatives in mostly good to high yields, and with a broad substrate scope. A mechanistic study suggested the formation of a semi-opened Ru(iii) intermediate chelating/activating the aldimine, and the occurrence of single-electron transfer (SET) to generate a vinyl radical, followed by vinylation and then an intramolecular 6π-electrocyclization of 1,3-hexatrene to form the product.

Digital colloid-enhanced Raman spectroscopy for the pharmacokinetic detection of bioorthogonal drugs.

Bioorthogonal drug molecules are currently gaining prominence for their excellent efficacy, safety and metabolic stability. Pharmacokinetic study is critical for understanding their mechanisms and guiding pharmacotherapy, which is primarily performed with liquid chromatography-mass spectrometry as the gold standard. For broader and more efficient applications in clinics and fundamental research, further advancements are especially desired in cheap and portable instrumentation as well as rapid and tractable pretreatment procedures.

Ultrathin NiO nanosheets anchored to a nitrogen-doped dodecahedral carbon framework for aqueous potassium-ion hybrid capacitors.

Hierarchical porous structures and well-modulated interfacial interactions are essential for the performance of electrode materials. The energy storage performance can be promoted by regulating the diffusion behavior of the electrolyte and constructing a coupled interaction at heterogeneous interfaces. Herein, we have synthesized ultrathin NiO nanosheets anchored to nitrogen-doped hierarchical porous carbon (NiO/N-HPC) and applied it to construct aqueous potassium ion hybrid capacitors (APIHCs).

Unlocking the chemical environment of nitrogen in perovskite-type oxides.

Nitrogen (N) doping of perovskite-type oxides is an effective method for enhancing their photocatalytic performance. Quantitative and qualitative analyses of the doped N species are essential for a deeper understanding of the catalytic activity enhancement mechanism. However, examining the N environment in perovskite-type oxides, particularly in the bulk, using conventional analytical techniques, such as X-ray photoelectron spectroscopy (XPS), is challenging.

Recent advances in CO reduction with renewable reductants under hydrothermal conditions: towards efficient and net carbon benefit CO conversion.

The ever-growing atmospheric CO concentration threatening the environmental sustainability of humankind makes the reduction of CO to chemicals or fuels an ideal solution. Two priorities are anticipated for the conversion technology, high efficiency and net carbon benefit, to ensure the mitigation of the CO problem both promptly and sustainably. Until now, catalytic hydrogenation or solar/electro-chemical CO conversion have achieved CO reduction promisingly while, to some extent, compromising to fulfill the two rules, and thus alternative approaches for CO reduction are necessary.

Polyvinylidene fluoride/graphene oxide/polyimide composite high-efficiency PM filtration nanofiber membranes.

Particulate air pollution is a global environmental problem, with PM being the primary pollutant. One of the most effective ways to remove particles from the air is through filtration. Therefore, high-performance air filters are urgently needed to combat the harm caused by PM.

UV-assisted synthesis of ultra-small GO-Austar for efficient PTT therapeutic architectonic construction.

Conventional Au nanomaterial synthesis typically necessitates the involvement of extensive surfactants and reducing agents, leading to a certain amount of chemical waste and biological toxicity. In this study, we innovatively employed ultra-small graphene oxide as a reducing agent and surfactant for the generation of small Au nanoparticles under ultraviolet irradiation (UV) at ambient conditions. After ultra-small GO-Au seeds were successfully synthesized, we fabricated small star-like Au nanoparticles on the surface of GO, in which GO effectively prevented Austar from aggregation.

Axially chiral styrene-based organocatalysts and their application in asymmetric cascade Michael/cyclization reaction.

An axially chiral styrene-based organocatalyst, featuring a combination of axially chiral styrene-based structure and a pyrrole ring, has been designed and synthesized. This catalyst demonstrates remarkable capabilities in producing a wide range of densely substituted spirooxindoles that feature an alkyne-substituted quaternary stereogenic center. These spirooxindoles are generated through mild cascade Michael/cyclization reactions, resulting in high conversion rates and exceptional enantioselectivity.

Stereoselective alkyl -glycosylation of glycosyl esters anomeric C-O bond homolysis: efficient access to -glycosyl amino acids and -glycosyl peptides.

-Glycosyl peptides possess excellent metabolic stability and therapeutic properties and thus play critical roles in biological studies as well as drug discoveries. However, the limited accessibility of -glycosyl amino acids has significantly hindered the broader research of their structural features and mode of action. Herein, for the first time we disclose a novel visible-light-driven radical conjugate addition of 1,4-dihydropyridine (DHP)-derived glycosyl esters with dehydroalanine derivatives, generating -glycosyl amino acids and -glycosyl peptides in good yields with excellent stereoselectivities.

Nanoarchitectonics on Z-scheme and Mott-Schottky heterostructure for photocatalytic water oxidation dual-cascade charge-transfer pathways.

The bottleneck for water splitting to generate hydrogen fuel is the sluggish oxidation of water. Even though the monoclinic-BiVO (m-BiVO)-based heterostructure has been widely applied for water oxidation, carrier recombination on dual surfaces of the m-BiVO component have not been fully resolved by a single heterojunction. Inspired by natural photosynthesis, we established an m-BiVO/carbon nitride (CN) Z-scheme heterostructure based on the m-BiVO/reduced graphene oxide (rGO) Mott-Schottky heterostructure, constructing the face-contact CN/m-BiVO/rGO (CNBG) ternary composite to remove excessive surface recombination during water oxidation.

Nanofluidic proton channels based on a 2D layered glass membrane with improved aqueous and acid stability.

Layered two-dimensional (2D) membranes hold great promise in the study of confined ion transport and nanofluidic applications. However, 2D layered membranes suffer from poor stability in water and harsh chemical conditions. Here we use amorphous silica-based nanosheets obtained by vermiculite to assemble a layered glass membrane (LGM) with a 2D nanofluidic channel network in the interlayer space.

A novel rose-with-thorn ternary MoS@carbon@polyaniline nanocomposite as a rechargeable magnesium battery cathode displaying stable capacity and low-temperature performance.

Developing high-performance cathode materials for magnesium (Mg) batteries is of great significance. Here, a novel rose-with-thorn ternary MoS@C@polyaniline (PANI) nanocomposite composed of carbon and PANI nanoneedles co-coated on rose-like MoS is developed. The conductive PANI needles on the surface of MoS improve the conductivity, and the inner MoS is wrapped by a carbon layer which is beneficial for the aniline coating.

Revisiting the factors influencing the magnetic resonance contrast of GdO nanoparticles.

Gadolinium oxide nanoparticles (GONs) have the potential to be one of the best candidates for the contrast agents of magnetic resonance imaging. Even though the influence of parameters on the relaxation has been substantially demonstrated, the variation of the of GONs with a similar structure and surface chemistry implied our limited understanding. We herein synthesized GONs with adjustable size, shape, and crystallinity, modified them with a series of molecules with different acidities, and recorded their values and imaging contrast.

Molecular dynamics simulation insights into the cellular uptake of elastic nanoparticles through human pulmonary surfactant.

The interaction between inhaled nanoparticles (NPs) and the pulmonary surfactant (PS) monolayer has drawn significant attention due to its potential in drug delivery design and application for respiratory therapeutics in active and passive cellular uptake pathways. Even though much attention has been given to explore the interaction between NPs and the PS monolayer, the effects of the NP elasticity on the translocation across the PS monolayer have not been thoroughly studied. Here, we performed a series of coarse-grained (CG) molecular dynamics simulations to study active or passive cellular uptake pathways of three NPs with different elasticities through a PS monolayer.

Enhanced stability of nitrogen doped porous carbon fiber on cathode materials for high performance lithium-sulfur batteries.

Lithium-sulfur (Li-S) batteries are considered to be one of the candidates for high-energy density storage systems due to their ultra-high theoretical specific capacity of 1675 mA h g. However, problems of rapid capacity decay, sharp expansion in volume of the active material, and the shuttle effect have severely restricted their subsequent development and utilization. Herein, we design a nitrogen-doped porous carbon nanofiber (NPCNF) network as a sulfur host by the template method.

Lipid-Polymer Hybrid "Particle-in-Particle" Nanostructure Gene Delivery Platform Explored for Lyophilizable DNA and mRNA COVID-19 Vaccines.

SARS-CoV-2 has led to a worldwide pandemic, catastrophically impacting public health and the global economy. Herein, a new class of lipid-modified polymer poly (β-amino esters) (L-PBAEs) is developed via enzyme-catalyzed esterification and further formulation of the L-PBAEs with poly(d,l-lactide-coglycolide)--poly(ethylene glycol) (PLGA-PEG) leads to self-assembly into a "particle-in-particle" (PNP) nanostructure for gene delivery. Out of 24 PNP candidates, the top-performing PNP/C12-PBAE nanoparticles efficiently deliver both DNA and mRNA in vitro and in vivo, presenting enhanced transfection efficacy, sustained gene release behavior, and excellent stability for at least 12 months of storage at -20 °C after lyophilization without loss of transfection efficacy.

Cu(ii)/SPDO complex catalyzed asymmetric Baeyer-Villiger oxidation of 2-arylcyclobutanones and its application for the total synthesis of eupomatilones 5 and 6.

A novel classical kinetic resolution of 2-aryl-substituted or 2,3-disubstituted cyclobutanones of Baeyer-Villiger oxidation catalyzed by a Cu(ii)/SPDO complex is reported for the first time, producing normal lactones in excellent enantioselectivities (up to 96% ee) and regioselectivities (up to >20/1), along with unreacted ketones in excellent enantioselectivities (up to 99% ee). The current transformation features a wide substrate scope. Moreover, catalytic asymmetric total syntheses of natural eupomatilones 5 and 6 are achieved in nine steps from commercially available 3-methylcyclobutan-1-one.

The SARS-CoV-2 B.1.618 variant slightly alters the spike RBD-ACE2 binding affinity and is an antibody escaping variant: a computational structural perspective.

Continuing reports of new SARS-CoV-2 variants have caused worldwide concern and created a challenging situation for clinicians. The recently reported variant B.1.

Understanding the effect of HF-based wet shallow etching on optical performance of reactive-ion-etched fused silica optics.

The optical performance of fused silica optics used in high-power lasers is known to depend not only on their surface damage resistance, but also on their surface quality. Previous studies have shown that good fused silica damage performance and surface quality can be achieved by the use of reactive ion etching (RIE), followed by HF-based wet shallow etching (3 μm). In this study, two kinds of HF-based etchants (aqueous HF and HF/NHF solutions) were employed to investigate the effect of HF-based etching on the optical performance of reactive-ion-etched fused silica surfaces at various HF-based shallow etching depths.

Application of decarboxylation reactions for improvement of dielectric properties of a methacrylic polymer.

In this work, we present a method based on thermally induced decarboxylation to solve the incompatibility of dielectric properties and the developability in aqueous developer solution of dielectric materials for the application in photodefinable insulating materials. Herein, malonic acid 2-hydroxyethyl methacrylate monoester, a methacrylate monomer with β-keto acid is synthesized phosphotungstic acid catalyzed esterification of 2-hydroxyethyl methacrylate and malonic acid. Further polymerisation is conducted with the obtained monomer to prepare poly(2-hydroxyethyl methacrylate--malonic acid 2-hydroxyethyl acrylate monoester).

Electrochemical detection of mercuric(ii) ions in aqueous media using glassy carbon electrode modified with synthesized tribenzamides and silver nanoparticles.

This study reports the synthesis, characterization, and mercuric ion detection ability of novel tribenzamides having flexible and rigid moieties. -{4-[2-(1,3-Benzoxazolyl)]phenyl}-3,5-,'-bis(4-alkyloxybenzoyl)benzamides (TBa-TBc) were synthesized from newly synthesized diamine, -(1,3-benzoxazol-2-yl-phenyl)-3,5-diaminobenzamide (BODA) and -alkoxybenzoic acids (-ABA) by amidation reaction. Structural characterization of the synthesized compounds was done through spectroscopic techniques (FT-IR and NMR).

A porous silicon anode prepared by dealloying a Sr-modified Al-Si eutectic alloy for lithium ion batteries.

Silicon has been considered to be one of the most promising anode materials for next generation lithium ion batteries due to its high theoretical specific capacity. However, its huge volume expansion during the lithiation/delithiation process that can result in rapid capacity fading and low conductivity present significant challenges for application. In this study, the morphology of Si in an Al-Si eutectic alloy was modified by Sr, and porous Si was then produced by dealloying the precursor.