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The scaled-up synthesis of organic-free monolayer nanomaterials is highly desirable, especially in obtaining green energy by electrocatalysis. In this study, a method for the scaled-up synthesis of the series of monolayer layered double hydroxides (LDHs) without the addition of organic solvents is reported via the separate nucleation and aging steps process. The resulting monolayer LDHs with the thicknesses of less than 1 nm showed a narrow thickness distribution. X-ray absorption fine-structure revealed that monolayer NiFe-LDH nanosheets have a number of oxygen and metal vacancies defects. As a practical application, monolayer NiFe-LDH nanosheets containing defects showed an enhanced electrocatalytic water oxidation activity compared with that of bulk NiFe-LDH. Density functional theory calculations uncovered that excellent catalytic activity is attributed to vacancies defects. The proposed method is an economical and universally applicable strategy for the scaled-up production of monolayer LDHs.

A triangular prism cage 2 with benzene triimide (BTI) as the base and 2,7-naphthalene dimethylene as the supporting pillars was designed and synthesized efficiently. The two parallel BTI planes con...

Surfactants with polyoxometalates (POMs) as polar head groups have shown fascinating self-assembly behaviors and various functional applications. However, self-assembly them into reverse micelles is still challenging owing to the large molecular size and intermolecular strong electrostatic repulsions of POM heads. In this work, a zwitterionic POM-based surfactant was synthesized by covalently grafting two cationic long alkyl tails onto the lacunary site of [PW11O39]7−. With decreased electrostatic repulsions and increased hydrophobic effect, the POM-based reverse micelles with an average diameter of 5 nm were obtained. Interestingly, when these reverse micelles were applied for catalyzing the oxidation of styrene, an unprecedented β-hydroxyl peroxide compound of 2-hydroxyl-2-phenylethan-1-tert-butylperoxide was produced in high selectivity of 95.2%. In comparison, the cetyltrimethylammonium electrostatically encapsulated POMs mainly generated the epoxides or 1,2-diols. A free radical mechanism was proposed for the oxidation reaction catalyzed by the zwitterionic POM surfactants.

The first-order phase transition plays a pivotal role in material behaviors, yet that of carbides, a type of important materials, has not been systematically studied. Herein, the melting process and structural properties of binary iron carbide (FexCy) nanoparticles are characterized by reactive molecular dynamics simulation. It was found that the melting point of FexCy nanoparticle decreased with decreasing size and increased with increasing Fe/C ratio, which were consistent with the experimental results. The melting process starts at the surface and proceeds inwards. The carbon atoms are fully activated before reaching the melting point and the iron core melts last. At high temperatures, carbon atoms exhibit significant outward diffusion behavior and form carbon deposition on the surface. When the temperature exceeds the pre-melting point, although the high temperature gives the nanoparticles more atomic active sites with low coordination, the surface carbon accumulation, such as C2, blocks the active sites leading to a lower turn-over frequency of FexCy for CO dissociation. These findings provide an atomistic comprehension of the melting mechanisms and behaviors of binary FexCy nanoparticles, as well as a theoretical foundation for understanding their structural transformation as a catalyst, which is caused by the heat released from catalytic exothermic reactions.

Background: A liquid chromatography-tandem mass spectrometric (LC-MS/MS) method had been developed for the quantification of acotiamide in rat plasma and been applied to pharmacokinetic studies. However, there was no LC-MS/MS method been developed for the determination of acotiamide in human plasma and its pharmacokinetic study. Objective: A simple and fast LC-MS/MS method was established and validated for the quantification of acotiamide in human Received: plasma and was applied to a pharmacokinetic study. Methods: Sample preparation was accomplished Revised: Accepted: through protein precipitation, and chromatographic separation was achieved on a Welch, Ultimate XB-C18 column (2.1×50 mm, 3 μm) with a security guard cartridge C18 using a binary gradient with DOI: mobile phase A (Methanol) and B (the solution of 10 mM Ammonium acetate with 0.1% Formic acid) at a flow rate of 400 μL/min. Results: The retention time of acotiamide and its internal standard, acotiamide-d6 was 1.78 min and 1.79 min, respectively. The total run time was 4.0 min. The method was developed and validated over the concentration range of 0.500-100 ng/mL for acotiamide, with correlation coefficient greater than 0.9987. The extraction recovery was more than 108.43% and the matrix effect was not significant. The inter- and intra-day precisions were below 5.80% and accuracies ranged from 92.7 to 103.0%. Acotiamide was demonstrated to be stable in human plasma under the tested conditions. Conclusion: The validated LC-MS/MS method was successfully applied to study the pharmacokinetic profiles of acotiamide in human plasma after oral administration and has achieved satisfactory results.

As a family of two-dimensional functional materials, layered double hydroxides(LDHs) have the characteristics of adjustable lamellar element type and proportion, variable interlamellar anion, controllable particle size and thickness, providing a robust platform for photo/electro/thermal-catalysis. With the continuous progress of materials science, the synthesis of LDHs is becoming more and more refined. Herein, to achieve the fine preparation of LDHs materials, especailly for the no-chemical/material researchers, we successfully assembled the automatic synthesis device and wrote corresponding computer software to control this device, and the automatic synthesis of bulk and monolayer LDHs nanosheets on a laboratory scale can be realized. This work paves a new labor-saving way for the fine synthesis of LDHs nanostructures, further improving the development of LDHs-based materials.

The solution dynamics behavior of polyoxometalates (POMs) is essential to understand their catalytic mechanism under real conditions. Herein, the phase-transfer process of a novel catalyst PVDB-VBC...

Hydrazine (N2 H4 ) is considered as one of the most potential energy storage materials in liquid fuel cells, as it contains high energy and power density, and the high-efficiency oxidation of N2 H4 in fuel cells has drawn great attention. However, the most used catalysts are expensive noble metal catalysts, thus the development of highly efficient non-noble metal catalysts is crucial to reduce the cost of hydrazine oxidation in practical industry. Herein, we synthesized a series of CoFe-layered double hydroxides (CoFe-LDHs) intercalated with different anions via a simple one-step co-precipitation method for the electrooxidation of hydrazine. Through altering the intercalated anions of CoFe-LDHs, the defects and the electronic structure can be well controlled, and the catalytic performance for the electrooxidation of hydrazine were well promoted by using NO3- intercalated into CoFe-LDH compared with other anions (like Cl- , BO33- , CO32- ). This work developed a series of hydrazine electrooxidation catalysts and established the relationship between the intercalated anions, the fine structure of the catalyst and the electrocatalytic performance.

Here, we report an unprecedented catalytic enantioselective cyanation of ketonitrones enabled by the bifunctional cyanating reagent Me2(CH2Cl)SiCN. This approach allows facile access to optically active N-hydroxyl-α-amino nitriles that are of high synthetic value but difficult to acquire by other methods. The use of bifunctional cyanating reagent Me2(CH2Cl)SiCN not only achieves an enantioselectivity higher than that with TMSCN but also enables various diversification reactions of the resulting silylated adducts. This represents the first enantioselective catalytic nucleophilic addition reaction of unactivated ketone-derived nitrones, exhibiting the potential of such tetrasubstituted C═N bonds for asymmetric synthesis of N-hydroxy α-amino acids and other N-hydroxy tertiary amines.

Exploiting noncovalent π-interactions particularly emerging anion-π interactions to drive efficient catalysis is fascinating. Even with exciting progresses, can anion-π activation operate in water remains elusive. Here we report the design, synthesis and catalytic studies of a class of water-soluble electron-deficient molecular cages and relevant aromatic slide compounds. The prism-like cages contain three divided, long, cationic aromatic walls which constitute three highly electron-deficient V-shape cavities. They were efficiently synthesized in two steps from a parent triformyl cage in gram-scale. Crystal structure showed the π-walls bind to the counter bromide through strong anion-π interactions. Just 5 mol% of cages were effective in catalyzing decarboxylative Aldol reactions of aldehydes and malonic acid half thioesters in water but not in organic solvents, showing a pronounced hydrophobic amplification effect. Meantime, a series of single π-slides resembling the π-wall of the cage performed equally well, while those lacking an extended π-surface were ineffective, highlighting the essential role of electron-deficient π-face on promoting the conversion.

Direct conversion of methane (CH4 ) to fuels and other high value-added chemicals is an attractive technology in the chemical industry; however, practical challenges to sustainable processes remain. Herein, we report the preparation of a heterostructured Co-doped MgO-based catalyst through topological transformation of a MgCo-layered double hydroxide (LDH) calcination from 200 to 1100 °C. Remarkably, the catalyst can activate CH4 coupling to produce C2 H6 with a selectivity of 41.60 % within 3 h under full-spectrum irradiation through calcination of LDH at 800 °C. Characterization studies and catalytic results suggest that the highly dispersed active sites and large interfaces amongst the Co-doped MgO-based catalysts enable surface activation of CH4 to methyl (CH3 *), in turn promoting coupling of CH3 * to C2 H6 . This study introduces a promising pathway for photodriven CH4 coupling to give high value-added chemicals by using layered double hydroxides as a precursor.

Polyoxometalates (POMs)-based materials, with high theoretical capacities and abundant reversible multi-electron redox properties, are considered as promising candidates in lithium-ion storage. However, the poor electronic conductivity, low specific surface area and high solubility in the electrolyte limited their practical applications. Herein, a double-shelled hollow PMo12 -SiO2 @N-C nanofiber (PMo12 -SiO2 @N-C, where PMo12 is [PMo12 O40 ]3- , N-C is nitrogen-doped carbon) was fabricated for the first time by combining coaxial electrospinning technique, thermal treatment and electrostatic adsorption. As an anode material for LIBs, the PMo12 -SiO2 @N-C delivered an excellent specific capacity of 1641 mA h g-1 after 1000 cycles under 2 A g-1 . The excellent electrochemical performance benefited from the unique double-shelled hollow structure of the material, in which the outermost N-C shell cannot only hinder the agglomeration of PMo12 , but also improve its electronic conductivity. The SiO2 inner shell can efficiently avoid the loss of active components. The hollow structure can buffer the volume expansion and accelerate Li+ diffusion during lithiation/delithiation process. Moreover, PMo12 can greatly reduce charge-resistance and facilitate electron transfer of the entire composites, as evidenced by the EIS kinetics study and lithium-ion diffusion analysis. This work paves the way for the fabrication of novel POM-based LIBs anode materials with excellent lithium storage performance.

Background: High-performance liquid chromatography (HPLC) method has been used to detect related impurities of perampanel. However, the detection of impurities is incomplete, and the limits of quantification and detection are high. A sensitive, reliable method is in badly to be developed and applied for impurity detection of perampanel bulk drug. Objective: Methodologies utilising HPLC and gas chromatography (GC) were established and validated for quantitative determination of perampanel and its related impurities (a total of 10 impurities including 2 genotoxic impurities). Methods: The separation was achieved on a Dikma Diamonsil C18 column (250 mm × 4.6 mm, 5 μm) with the mobile phase of 0.01 mol/L potassium dihydrogen phosphate solution (A) and acetonitrile (B) in gradient elution mode. The compound 2-bromopropane was determined on an Agilent DB-624 column (0.32 mm × 30 m, 1.8 μm) by electron capture detector (μ-ECD) with split injection ratio of 1:5 and proper gradient temperature program. Result: Both HPLC and GC methods were established and validated to be sensitive, accurate and robust according to the International Council for Harmonization (ICH) guidelines. The methods developed were linear in the selected concentration range (R2≥0.9944). The average recovery of all impurities was between 92.6% and 103.3%. The possible production mechanism of impurities during the synthesis and degradation processes of perampanel bulk drug was also discussed. Five impurities were analyzed by liquid chromatography–mass spectrometry (LC-MS). Moreover, two of them were simultaneously characterized by LC-MS, IR and NMR. Conclusion: The HPLC and GC methods were developed and optimized, which could be applied for quantitative detection of the impurities, and further stability study of perampanel.

A versatile biocatalytic desymmetric method for efficiently accessing enantiopure cis-3,4-disubstituted pyrrolidines was developed. Catalyzed by amidase-containing E. coli whole cells, a series of meso pyrrolidine-2,5-dicarboxamides were hydrolyzed to obtain 4-carbamoylpyrrolidine-3-carboxylic acid derivatives in 47%–95% yields and 62% ∼ >99.5% ee values under mild condition. The catalytic efficiency and enantioselectivity are related to the substituents in the phenyl ring. The enzyme-substrate binding mode is established and the high enantioselectivity of amidase is revealed by MD simulations. The improvement of biocatalytic efficiency has been preliminarily explored through protein engineering.

Simply constructing multiple responsive polymers with obvious shape and dimension variations on their assemblies upon different stimuli is still rarely reported. In this study, we report a hyperbranched polymer named HPAzoBAHB-star-PEG9 with quadruple-response to light, temperature, pH and oxidation stimuli. The polymer contains azobenzene chromophore, sulfide, amide and amine groups in its hydrophobic hyperbranched core, and the core is capped with hydrophilic polyethylene glycol (PEG9) arms. HPAzoBAHB-star-PEG9 could assemble into unusual leaf-like lamellar micelles at 25 °C under the guidance of orderly arranged H-aggregate of azobenzene moieties. These leaf-like lamellar micelles can transform into vesicles upon UV irradiation and lower temperature, or convert to smaller spherical micelles in acidic or oxidative environments, respectively, with the destroy of ordered azobenzene arrangements. This quadruple-responsive hyperbranched polymer is suitable to construct multiple stimuli-responsive micro/nanostructures, or accurate delivery and release following subtle stimuli sequences.

A Cd(ΙI)-based luminescent coordination polymer, namely [Cd(L)2(H2O)2]n (1), has been synthesized by 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene ligand (HL) and structurally characterized. The selectiv...

Acid catalysis, one of the most important industrial processes, suffers from the toxicity, corrosion and recyclability problems of conventional homogeneous acid catalysts. Thus, the development of green heterogeneous acid catalysts becomes the focus of fundamental research and industrial catalysis. As a class of discrete anionic metal-oxygen clusters with tunable structure at the molecular and atomic scales, polyoxometalates (POMs) benefit from their super strong Bransted acidity, high proton mobility, and thermal stability. POMs-based heterogeneous catalysts have been used as the potential green alternatives to conventional homogeneous acid catalysts. In this review, we summarize recent progress on the design strategies of the POMs-based heterogeneous catalysts and their catalytic properties in acid-catalyzed reactions, where they are combined with functionalized cations, modified through covalent interactions, supported onto the non-precious metal support, and introduced into the framework of porous polymers. The design, functional strategies and catalytic performance of these POMs-based heterogeneous catalysts in specific acid-catalyzed reactions are emphasized.

In intercropping systems, high-positioned crops often exert shading stress on low-positioned crops, thus affecting the agronomic characteristics of the low-positioned crops. This study determined the mechanisms of photosynthetic, physiological and yield variations among peanut cultivars under shading stress. Four peanut cultivars, S60, C4, P12, and YS151, were grown in the field and subjected to shading stress for 77 days during reproductive stages. S60 and P12 showed lower yield and reduced biomass accumulation than C4 and YS151 under shading stress. Shading stress induced higher antioxidant enzyme activities in S60 and P12, relative to C4 and YS151. Under shading stress, S60 and P12 showed a higher light-trapping capability than C4 and YS151, which was associated with changes in chlorophyll (Chl) a and b contents, and Chl a/b ratio. The net photosynthetic rate, stomatal conductance and transpiration rates of C4 and YS151 were decreased, but the intercellular CO2 concentration increased under shading stress. The results demonstrated that non-stomatal limiting factors decreased the photosynthetic capacity of peanut under shading stress. The maximum photochemical efficiency of PSII (Fv/Fm) and non-photochemical quenching (NPQ) were higher in S60 and P12 than in C4 and YS151 under shading stress. These results suggest that S60 and P12 could absorb more light energy from weak light environments for photosynthesis than C4 and YS151 and dissipate the excess energy in the form of heat to improve their light protection ability. This study explains the inter-variety differences in shading stress tolerance in peanut and provides physiological parameters for guiding the selection of shade-tolerant cultivars.

As a biomass-derived polymer, cellulose acetate propionate (CAP) is widely used in food packaging, plastics and coatings, and so forth. In order to produce CAP in a green and environmentally benign...

Co(II) and Cu(II) complexes, [Co2(H2L)2(phen)2(H2O)4](H2O)2 (1) and [Cu2(L)0.5(phen)2Cl2]n (2) [H4L = 5,5'-(diazene-1,2-diyl)diisophthalic acid, phen = 1,10-phenanthroline], have been solvothermall...

Aims Invasive plants may alter soil fungal communities in a way that improves their growth. Nitrogen (N) content of soil affects the symbiosis between plants and arbuscular mycorrhizal fungi (AMF), further determining plant growth. Yet, it is unclear whether altered AMF communities change the dependence of invasive and native species on N-form, and whether N forms alter the invasive plant–AMF interaction (PSIM). Methods Two synthetic plant communities, including four Solidago canadensis individuals and four native plant species, were inoculated with AMF spores from S. canadensis-invaded soils and adjacent non-invaded soils, and were provided with nitrate, ammonia or glutamate. After their growth, the performance of the two plant communities in treatments of AMF origin and N forms, and the pathways of the N forms affecting S. canadensis growth and PSIM were evaluated. Important Findings Solidago canadensis had no obvious N-form dependence in any of the AMF inoculations. Native plant species showed weak N-form dependence, but invasive AMF could remove their N-form dependence. In the absence of N, AMF did not affect growth of S. canadensis and the native plants. In contrast, with N addition, invasive AMF significantly increased belowground and total biomass of the invasive plants but not those of the native plants. Positive PSIM of S. canadensis was also evidently greater than that of native plant species and was realized through directly or indirectly regulating phenotypic traits including plant height, leaf number and number of rhizomes. Our findings emphasize the importance of plant–AMF interactions and a unique N-acquisition strategy during plant invasions.

Two-dimensional (2D) nanosheets have been widely reported and applied. Among them, 2D VOPO4·2H2O (HVPO) is widely used in the chemical industry and energy storage field because of its polyanionic l...

Epoxidized soybean oil (ESO)-based thermosets are attracting increasing attention because they are derived from renewable resources. To date, unfortunately, they have not been able to replace petroleum-based epoxy resins yet due to their poor mechanical properties and unsatisfactory thermal performances. To address the drawbacks, quercetin (QC) as a biobased polyphenol-type curing agent was chosen to increase the rigidity of ESO-QC thermosets. Meanwhile, three imidazole-type accelerators, including N-methylimidazole (N-MI), 4-methylimidazole (4-MI), and biobased histidine (His), were introduced to reduce the activation energy during curing and to tailor the network structures after curing. All ESO-QC thermosets possessed excellent thermal stabilities, thanks to the high rigidity and cross-linking density, among which the initial decomposition temperature of ESO-QC/His was up to 348 °C. Due to the different topological structures of ESO-QC thermosets resulted from different catalytic mechanisms of N-MI and 4-MI, superior tensile and flexural strengths of 44.7 and 81.8 MPa were obtained in ESO-QC/4-MI thermosets, respectively, while the ESO-QC/N-MI thermosets displayed outstanding tensile modulus of 1058 MPa, which could rarely be discovered in biobased systems. In addition, the Izod unnotched impact strength of ESO-QC/His thermosets reached 23.5 kJ·m–2, which was even higher than that of the commercial petroleum-based epoxy resins. These features provide great potential for the sustainable polymers for versatile applications.

A novel kind of fully bio-based PSAs were obtained through the curing reaction between two components derived from the plant oils: carboxyl-terminated polyricinoleate (PRA) from the castor oil and epoxidized soybean oil (ESO). The gel content, glass transition temperature (Tg), rheological behavior, tensile strength, creep resistance and 180° peel strength of the PSAs were feasibly tailored by adjusting the component ratio of ESO to PRA. At low cross-linking level, the PSAs behaved like a viscous liquid and did not possess enough cohesiveness to sustain the mechanical stress during peeling. The PSAs cross-linked at or near the optimal stoichiometric conditions displayed an adhesive (interfacial) failure between the substrate and the adhesive layer, which were associated with the lowest adhesion levels. The PSAs with the dosage amount of ESO ranging from 10∼20 wt% were tacky and flexible, which exhibited 180° peel strength ranging from 0.4∼2.3 N/cm; and could be easily removed without any residues on the adherend. The process for the preparation of the fully bio-based PSAs was environmentally friendly without using any organic solvent or other toxic chemical, herein showing the great potential as sustainable materials.

In order to improve the wettability and bonding performance of the interface between carbon fiber and aluminum matrix, nickel- and copper-coated carbon fiber-reinforced aluminum matrix composites were fabricated by the squeeze melt infiltration technique. The interface wettability, microstructure and mechanical properties of the composites were compared and investigated. Compared with the uncoated fiber-reinforced aluminum matrix composite, the microstructure analysis indicated that the coatings significantly improved the wettability and effectively inhibited the interface reaction between carbon fiber and aluminum matrix during the process. Under the same processing condition, aluminum melt was easy to infiltrate into the copper-coated fiber bundles. Furthermore, the inhibited interface reaction was more conducive to maintain the original strength of fiber and improve the fiber–matrix interface bonding performance. The mechanical properties were evaluated by uniaxial tensile test. The yield strength, ultimate tensile strength and elastic modulus of the copper-coated carbon fiber-reinforced aluminum matrix composite were about 124 MPa, 140 MPa and 82 GPa, respectively. In the case of nickel-coated carbon fiber-reinforced aluminum matrix composite, the yield strength, ultimate tensile strength and elastic modulus were about 60 MPa, 70 MPa and 79 GPa, respectively. The excellent mechanical properties for copper-coated fiber-reinforced composites are attributed to better compactness of the matrix and better fiber–matrix interface bonding, which favor the load transfer ability from aluminam matrix to carbon fiber under the loading state, giving full play to the bearing role of carbon fiber.

Comprehension upon the mechanism of oxidative deactivation of carbides is of significance for extending their applications, in particular, for developing Fe-based catalysts with outstanding perform...

The rational design of highly efficient bifunctional electrocatalysts for water splitting is extremely urgent for application in sustainable energy conversion processes to alleviate the energy crisis and environmental pollution. In this work, through simple deposition of layered double hydroxides (LDH) on Co3 O4 /NF (NF=nickel foam) nanosheets arrays, hierarchical Co3+ -rich materials based on LDH-Co3 O4 /NF are prepared as highly active and stable electrocatalysts for water splitting. The NiFe-LDH-Co3 O4 /NF demonstrates excellent electrochemical activity with an overpotential of 214 mV for the OER and an overpotential of 162 mV for the HER at 10 mA cm-2 . Such a performance is attributed to the optimized electronic states with a high concentration of Co3+ , which improves the intrinsic activity, and the sheet-on-sheet hierarchical structure, which increases the number of active sites. The unique synchronous design of both the architectural and electronic structure of nanomaterials can simultaneously accelerate the reaction kinetics and provide a more convenient charge transfer path. Therefore, the strategy reported herein may open a new pathway for the design of excellent electrocatalysts for water splitting.

3-Methyl-6-(3,5-difluorophenyl)imidazo[2,1-b]thiazole (mdfpit) and 3-methyl-6-(3,4,5-trifluorophenyl)imidazo[2,1-b]thiazole (mtfpit) were easily prepared from thiourea, acetone, and 3,5-difluorobenzoyl bromide or 3,4,5-trifluorobenzoyl bromide. These were used as primary ligands to synthesize twelve phosphorescent IrIII complexes with picolinic acid (pic), isoquinoline-3-carboxylic acid (3-IQA), quinoline-2-carboxylic acid (2-QA), 2-(pyridin-2-yl)phenol (2-ylppy), 2-(2,4-difluorophenyl)pyridine (dfppy), and pyridine-2-sulfonic acid (2-sappy) as auxiliary ligands. Their structures, photoluminescence, and electrochemical properties were investigated. Upon introducing more fluorine atoms into the benzene ring of the primary ligand, the thermal stability, photoluminescence quantum yield (PLQY), LUMO energy level, and luminous efficiency of the resulting IrIII complexes are significantly improved, and the photoluminescence emission spectra are blue-shifted. Their maximum emission wavelengths are present in the range of 517–618 nm, and the luminous colors span from the green to red light region. Using the synthesized IrIII complexes as emitters, LED chips based on InGaN chip excitation were developed, which showed good performances. Among all LEDs, the PLQY of the (mtfpmt)2Ir(pic) based LED is 58.4%, and the luminous efficiency is as high as 17.11 lm W−1; the luminous efficiency of the (mdfpmt)2Ir(2-QA) based LED is 3.41 lm W−1 with CIE coordinates of 0.60 and 0.38, which are very similar to the saturated standard red light emission. The results demonstrate the potential of the studied IrIII complexes as candidates for LED materials.

Benzaldehyde is a highly desirable chemical due to its extensive application in medicine, chemical synthesis and food sector among others. However, its production generally involves hazardous solvents such as trifluorotoluene or acetonitrile, and its conversion, especially selectivity in the aqueous phase, is still not up to expectations. Hence, developing an environmentally benign, synthetic process for benzaldehyde production is of paramount importance. Herein, we report the preparation of a photocatalyst (PW12-P-UCNS, where PW12 is H3PW12O40·xH2O and P-UCNS is phosphoric acid-modified unstack graphitic carbon nitride) by incorporating phosphotungstic acid on phosphoric acid-functionalised graphitic carbon nitride (g-C3N4) nanosheets. The performance of PW12-P-UCNS was tested using the benzyl alcohol photo-oxidation reaction to produce benzaldehyde in H2O, at room temperature (20 °C). The as-prepared PW12-P-UCNS photocatalyst showed excellent photocatalytic performance with 58.3% conversion and 99.5% selectivity within 2 h. Moreover, the catalyst could be reused for at least five times without significant activity loss. Most importantly, a proposed Z-scheme mechanism of the PW12-P-UCNS-catalysed model reaction was revealed. We carefully investigated its transient photocurrent and electrochemical impedance, and identified superoxide radicals and photogenerated holes as the main active species through electron spin-resonance spectroscopy and scavenger experiments. Results show that the designed PW12-P-UCNS photocatalyst is a highly promising candidate for benzaldehyde production through the photo-oxidation reaction in aqueous phase, under mild conditions.

Synthesis of syngas (CO, H2) by photocatalytic reduction of CO2 and H2O represents an eco-friendly pathway for large-scale CO2 utilization for the production of chemical raw materials with high added value. However, the precise control of the CO : H2 ratio from 1 : 1 to the stoichiometric ratio of 1 : 3 is a major challenge in the process of photocatalytic CO2 reduction, especially under long-wavelength irradiation (like green light of 550 nm). Herein, under visible light (λ > 400 nm), a heterostructured layered double hydroxide nanosheets/TiC (denoted as LDH/TiC) photocatalyst was prepared and exhibited tunable syngas synthesis with different CO/H2 ratios (from 1 : 1–1 : 3). More importantly, such performance can be well controlled even under green light irradiation (550 nm) in conjunction with a Ru-complex photosensitizer and triethanolamine (TEOA) as a sacrificial agent. Theory calculations revealed that the excellent performance came from the assembly between LDH and TiC, which could not only improve the charge transfer efficiency but also change the desorption energy of H2, resulting in the precise tunable ratio of syngas. This work offers an excellent strategy to design photocatalysts for reducing CO2 to syngas for potential applications.

The cytotoxicity of isosteviol and its twenty derivatives on three human tumor cell lines (ECA-109, MCF-7 and B16-F10) were evaluated. The results demonstrated that ECA-109 was the most sensitive cell line which was exposed to the compound (VI) with the lowest IC50 value of 1.30 ± 0.11 μM. By quantitative structure–activity relationship (QSAR) technique, the obtained cytotoxicity data were further utilized to respectively generate the statistically reliable HQSAR model (q2 = 0.828, r2 = 0.941, $$r_{{{\text{pred}}}}^{{\text{2}}}$$ = 0.849) and topomer CoMFA model (q2 = 0.608, r2 = 0.919, $$r_{{{\text{pred}}}}^{{\text{2}}}$$ = 0.747), which could provide the guidelines for the further development of novel and potent anti-esophageal agent.

Noble metal-based catalysts have attracted huge attention owing to their intriguing activity and selectivity. Revealing noble metal active sites and keeping them in a form of stable and high loading are crucial to improving the catalytic performance and understanding the reaction mechanism. Herein, a feasible preparation method was used to synthesize a Rh-based ultrathin NiFe layered double hydroxide (Rh/NiFe). The detailed study proved that the existence form of Rh atoms is atomically dispersed. Moreover, extended X-ray absorption fine structure (EXAFS) with theoretical calculation of X-ray absorption near-edge structure (XANES) and density functional theory (DFT) were used to identify at the atomic level the precise location and coordination environment of the introduced Rh atoms. It was found that Rh atoms are doped in the LDH layer in a coplanar position with Ni and Fe atoms. With a 5.4 wt% loading amount of Rh, the modified catalyst of Rh/NiFe-5.4 requires 80 mV less than unmodified ultrathin NiFe layered double hydroxide (NiFe) for hydrazine electrooxidation. The XAFS fitting revealed that the doping of Rh atoms results in the distortion of the laminate and then introduces certain defects, which may be attributed to electron transport, thus endowing them with exceptional electrocatalytic performance.

Keggin clusters are the most widely used polyoxometalate building blocks for the construction advanced materials, but effective methods for precisely recognizing the isostructural analogues of Keggins are still limited. In this study we employed the zwitterionic molecule 4,4'-dipyridyl N,N'-dioxide as a recognition receptor to specifically bind to the three Keggin analogues PW12 O403- , PMo12 O403- , and SiW12 O404- , which separately co-assembled into three different types of spherical charged colloids of different sizes. The recognition phenomena were confirmed by electrochemical methods and their crystallization behavior. Compared with solely anion-cation interaction-driven systems, the synergism with the anion-π interactions between the superchaotropic Keggins and the electron-deficient pyridine rings is believed to enhance the recognition. This observation is intriguing as the long-range solution assembly of Keggins is mainly driven by short-range anion-π interactions. Our results show that the little-noticed hydration shell of Keggins is significantly influenced by the superchaotropic effect, leading to differentiated binding affinity to the receptors and more obvious recognition phenomena between tungsten/molybdenum Keggin analogues.

Viral myocarditis (VMC) commonly triggers heart failure, for which no specific treatments are available. This study aims to explore the specific role of long non‐coding RNA (lncRNA) maternally expressed 3 (MEG3) in VMC. A VMC mouse model was induced by Coxsackievirus B3 (CVB3). Then, MEG3 and TNF receptor‐associated factor 6 (TRAF6) were silenced and microRNA‐223 (miR‐223) was over‐expressed in the VMC mice, followed by determination of ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS). Dual‐luciferase reporter assay was introduced to test the interaction among MEG3, TRAF6 and miR‐223. Macrophages were isolated from cardiac tissues and bone marrow, and polarization of M1 or M2 macrophages was induced. Then, the expressions of components of NLRP3 inflammatory body (NLRP3, ASC, Caspase‐1), M1 markers (CD86, iNOS and TNF‐α) and M2 markers (CD206, Arginase‐1 and Fizz‐1) were measured following MEG3 silencing. In the VMC mouse model, MEG3 and TRAF6 levels were obviously increased, while miR‐223 expression was significantly reduced. Down‐regulation of MEG3 resulted in the inhibition of TRAF6 by promoting miR‐223. TRAF6 was negatively correlated with miR‐223, but positively correlated with MEG3 expression. Down‐regulations of MEG3 or TRAF6 or up‐regulation of miR‐223 was observed to increase mouse weight, survival rate, LVEF and LVFS, while inhibiting myocarditis and inflammation via the NF‐κB pathway inactivation in VMC mice. Down‐regulation of MEG3 decreased M1 macrophage polarization and elevated M2 macrophage polarization by up‐regulating miR‐223. Collectively, down‐regulation of MEG3 leads to the inhibition of inflammation and induces M2 macrophage polarization via miR‐223/TRAF6/NF‐κB axis, thus alleviating VMC.

Photoreduction of CO2 into solar fuels is usually regarded as one of the promising solutions to overcome environmental pollution and the energy crisis. The main challenge in CO2 photoreduction (CO2 PR) is the low efficiency and poor selectivity. Layered double hydroxides (LDHs) are a class of 2D materials, consisting with M(OH)6 octahedra in the host layers and intercalated anions. Owing to the tuneable composition, particle size, morphology, and virtue coordinatively unsaturated active sites, a series of efficient strategies (morphology control, heterostructure, defect control, etc.) in LDH-based photocatalysts have been efficiently developed to enhance the photocatalytic selectivity and activity for CO2 PR. This review summarizes recent progress on the LDH-based photocatalysts for CO2 PR.

Diabetes is a disorder of glucose metabolism, and over 90% are type 2 diabetes. Diabetic cardiomyopathy (DCM) is one of the type 2 diabetes complications, usually accompanied by changes in myocardial structure and function, together with cardiomyocyte apoptosis. Our study investigated the effect of curcumin on regulating oxidative stress (OS) and apoptosis in DCM. In vivo, diabetes was induced in an experimental rat model by streptozoticin (STZ) together with high‐glucose and high‐fat (HG/HF) diet feeding. In vitro, H9c2 cardiomyocytes were cultured with high‐glucose and saturated free fatty acid palmitate. Curcumin was orally or directly administered to rats or cells, respectively. Streptozoticin ‐induced diabetic rats showed metabolism abnormalities and elevated markers of OS (superoxide dismutase [SOD], malondialdehyde [MDA], gp91phox, Cyt‐Cyto C), enhanced cell apoptosis (Bax/Bcl‐2, Cleaved caspase‐3, TUNEL‐positive cells), together with reduced Akt phosphorylation and increased Foxo1 acetylation. Curcumin attenuated the myocardial dysfunction, OS and apoptosis in the heart of diabetic rats. Curcumin treatment also enhanced phosphorylation of Akt and inhibited acetylation of Foxo1. These results strongly suggest that apoptosis was increased in the heart of diabetic rats, and curcumin played a role in diabetic cardiomyopathy treatment by modulating the Sirt1‐Foxo1 and PI3K‐Akt pathways.

In this paper, as a possible alternative to conventional petroleum-based pressure-sensitive adhesives (PSAs), a fully bio-based PSA with tunable adhesivity was designed and prepared, and the struct...

Solid oxide fuel cells (SOFCs) based on Ni-based cermet anodes suffer from severe sulfur poisoning when operated on H2S-containing fuels (

Solid oxide fuel cells (SOFCs) as one of the clean electrochemical energy conversion devices have acquired increasing attention recently due to the high efficiency, low emission, and excellent fuel...

The rational design of photocatalyst that can effectively reduce CO2 under visible light (λ > 400 nm), and simultaneously precise control of the products syngas (CO/H2) ratio is highly desirable for the Fischer-Tropsch reaction. In this work, we synthesized a series of CeO2-decorated layered double hydroxides (LDHs, Ce-x) samples for photocatalytic CO2 reduction. It was found that the selectivity and productivity of CO and H2 from photoreduction of CO2 in conjunction with Ru-complex as photosensitizer performed an obvious “volcano-like” trend, with the highest point at Ce-0.15 and the CO/H2 ratio can be widely tunable from 1/7.7 to 1/1.3. Furthermore, compared with LDH, Ce-0.15 also drove photocatalytic CO2 to syngas under 600 nm irradiation. It implied that an optimum amount of CeO2 modifying LDH promoted the photoreduction of CO2 to syngas. This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation.

The development of clean and efficient energy conversion and storage systems is becoming increasingly vital as a result of accelerated global energy consumption. Solid oxide fuel cells (SOFCs) as one key class of fuel cells have attracted much attention, owing to their high energy conversion efficiency and low emissions. However, some serious problems appeared because of the scorching operating temperatures of SOFCs (800–1000 °C), such as poor thermomechanical stability and difficult sealing, resulting in a short lifespan and high cost of SOFCs. Therefore, lowering the operating temperature of SOFCs to mid-range and even low range has become one of the main goals for SOFC development in the recent years. Looking for new cathode materials with high electrocatalytic activity and robust stability at relatively low temperatures is one of the essential requirements for intermediate-to-low-temperature SOFCs (ILT-SOFCs). During the past 15 years, we put considerable efforts into the development of alternative cathode materials for ILT-SOFCs. In this review, we give a summary of our progress from such efforts. We first summarize several strategies that have been adopted for developing cathode materials with high activity and durability toward reducing operating temperatures of SOFCs. Then, our new ideas and progress on cathode development with respect to activity and stability are provided. Both the cathodes of oxygen-ion-conducting SOFCs and protonic-conducting SOFCs are discussed. In the end, we outline the opportunities, challenges, and future approaches for the development of cathodes for ILT-SOFCs.

The reduction of C═C is of great importance, while H2 is the most widely used source usually in the harsh condition in the industry. However, under mild conditions, the H2-free reduction of C═C bon...

Endowing achiral polyoxometalates (POMs) with asymmetric catalytic properties is always an intriguing but challenging topic because of their high catalytic activities yet highly symmetrical molecular structures. In this work, a novel strategy was proposed to fabricate a series of two-dimensional chiral POM catalysts. Following the steps of exfoliation, covalent modification, and reassembly, the achiral POMs were orderly confined into the chiral interstitial domains of chiral ionic liquid (CIL)-modified layered double hydroxide materials with a decreased molecular symmetry. The chirality of POM molecules was induced by the l- or d-pyrrolidine-type CILs, and their asymmetric catalytic activity was enhanced by the confinement effect. Compared with the reported chiral POM-based catalysts [e.g., 8 turnover frequency (TOF) and 79% enantiomeric excess (ee) for chiral POM-based metal-organic frameworks], the constructed chiral POM catalysts showed a significantly higher TOF and enantioselectivity (up to 240 TOF and 93% ee) for the asymmetric epoxidation of allylic alcohols. The facilitated mass transfer in the IL channels and the increased binding efficiency between the chiral catalytic sites and reactants render this strategy highly promising for constructing efficient chiral catalysts from the catalytically active while achiral building blocks.

Photocatalytic reduction of CO2 with H2O to syngas is an effective way for producing high value-added chemical feedstocks such as methanol and light olefins in industry. Nevertheless, the precise control of CO/H2 ratio from photocatalytic CO2 reduction reaction still poses a great challenge for the further application. Herein, we prepared a series of highly efficient heterostructure based on highly dispersed palladium supported on ultrathin CoAl-layered double hydroxide (LDH). In conjunction with a Ru-complex sensitizer, the molar ratios of CO/H2 can be tuned from 1:0.74 to 1:3 under visible-light irradiation (λ > 400 nm). More interestingly, the syngas can be obtained under light irradiation at λ > 600 nm. Structure characterization and density functional theory calculations revealed that the remarkable catalytic activity can be due to the supported palladium, which improved the charge transfer efficiency. Meanwhile, more H atoms were used to generate H2 on the supported palladium for further tunable CO/H2 ratio. This work demonstrates a new strategy for harnessing abundant solar-energy to produce syngas from a CO2 feedstock.