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Constructing an internal electric field (IEF) within the hematite (Fe2O3) photoanode for highly efficient water oxidation performance with facilitated charge transfer and separation remains still a significant challenge. Unlike the conventional approach of creating interfacial electric fields through heterojunction design by introducing another semiconductor, a novel strategy is proposed for engineering localized n‐p homojunctions on the surface of Fe2O3 photoanode using gradient Zn2+ doping strategy. By implementing this approach, the inherent n‐type characteristics of Fe2O3 can be transformed into p‐type, thereby facilitating the formation of an n‐p junction with robust IEF, which enables more efficient charge separation and transfer. Additionally, the gradient Zn2+ doping is accompanied by the generation of oxygen vacancies, which further improves the charge transfer efficiency and accelerates water oxidation kinetics. As expected, the photocurrent density of optimized Fe2O3 photoanode at 1.23 V versus reversible hydrogen electrode is ≈2.6‐fold that of Fe2O3. This work provides a novel perspective on the design of localized n‐p homojunction within photoanodes for achieving high solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Constructing heterostructural photoanodes is attractive for elevating the photoelectrochemical (PEC) performance, however, it is a long‐standing challenge to achieve highly efficient interfacial charge transfer. Herein, a CoFe metal‐thiolate framework (CoFe MTF)/Fe2O3 photoanode connected by an interfacial Fe─O─N/S bond is designed to modulate the behavior of charge carriers and improve water oxidation performance. It is disclosed that this interfacial bond functions as a direct charge transfer bridge between shallow trap states of Fe2O3 and CoFe MTF, leading to prolonged carrier recombination lifetimes (85 ns for CoFe MTF/Fe2O3 compared to 37 ns for Fe2O3) and enhanced charge transfer efficiency. Alternatively, a robust interfacial electric field is established in the CoFe MTF/Fe2O3 p–n heterojunction, facilitating efficient charge transfer. As expected, the CoFe MTF/Fe2O3 photoanode exhibits significant enhancement in water oxidation, resulting in a three‐fold increase in photocurrent density compared to pristine Fe2O3. This study highlights the significance of designing interfacially bonded heterostructural photoelectrodes to regulate the transfer characters of charge carriers. [ABSTRACT FROM AUTHOR]

One new citrinin monomer derivative (1), and two new natural products α-pyrone analogues (2a and 2b), were isolated from the sponge derived fungus Penicillium sp. SCSIO 41302. Their structures were determined by extensive spectroscopic analysis, chiral-phase HPLC analysis, modified Mosher's method, ECD calculations, and X-ray single-crystal diffraction. Bioactivity screening showed that compounds 2b and 8 exhibited obvious inhibitory activities against pancreatic lipase and acetyl cholinesterase with IC50 values of 48.5 and 4.8 μM, respectively, which indicated that different chiral center between enantiomers (2a and 2b) might result in different biological activities (IC50 value against PL for 2a >100 μg/ml). [ABSTRACT FROM AUTHOR]

A new diketopiperazine, cyclo-(d-8-acetoxyl-Pro-l-Leu) (1), together with eight known compounds (2–9) including three enterotoxins (2–4), four diketopiperazines (5–8) and maltol (9), were isolated from the mangrove derived-soil Streptomyces sp. SCSIO 41400. The planar structures of all compounds were determined from analysis of NMR spectra, MS, optical rotation and comparing with literature data. The absolute configuration of compound 1 was assigned by electronic circular dichroism (ECD). The isolated compounds (1–9) were tested for their acetyl cholinesterase (AChE) and pancreatic lipase (PL) enzyme inhibitory activities. Among them, the new diketopiperazine (1) displayed preferable PL enzyme inhibitory activity with IC50 value of 27.3 μg/mL, while compounds 2, 5 and 6 showed weak PL enzyme inhibitory activity. Further molecular docking simulation exhibited that compound 1 could be well bind with the catalytic pocket of the PL. Besides, compound 9 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with MIC value of 12.5 μg/mL, which was comparable to that of the positive control ampicillin with MIC value of 3.125 μg/mL. [ABSTRACT FROM AUTHOR]

Lithium-oxygen batteries with ultrahigh energy density have received considerable attention as of the future energy storage technologies. The development of effective electrocatalysts and a corresponding working mechanism during cycling are critically important for lithium-oxygen batteries. Here, a single cobalt atom electrocatalyst is synthesized for lithium-oxygen batteries by a polymer encapsulation strategy. The isolated moieties of single atom catalysts can effectively regulate the distribution of active sites to form micrometre-sized flower-like lithium peroxide and promote the decomposition of lithium peroxide by a one-electron pathway. The battery with single cobalt atoms can operate with high round-trip efficiency (86.2%) and long-term stability (218 days), which is superior to a commercial 5 wt% platinum/carbon catalyst. We reveal that the synergy between a single atom and the support endows the catalyst with excellent stability and durability. The promising results provide insights into the design of highly efficient catalysts for lithium-oxygen batteries and greatly expand the scope of future investigation. Li–O2 batteries represent one of the promising paths toward high energy density battery systems. Here the authors synthesize single atom Co electrocatalysts to regulate the formation and decomposition of the major discharge product Li2O2, realizing high round-trip efficiency and stability in a Li–O2 cell. [ABSTRACT FROM AUTHOR]

Functionalization of metal-oxide semiconductors by noble metal nanoparticles is one of the most efficient methods for enhancing the gas-sensing property of semiconducting sensors. Herein, we synthesized a series of Au-loaded hierarchical WO3 hollow microspheres (Au-WO3) via a facile modified solvothermal method combining with wet impregnation method. The structure, elemental composition, and morphology of the synthesized materials were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscopy. The results show that the materials are uniform and independent WO3 hollow microspheres, and Au nanoparticles are well distributed on the surface of WO3. The gas sensing properties of Au-WO3 materials were investigated and the results suggest that Au loading could greatly improve gas sensing performance of WO3 to aromatic compounds, especially toluene and xylene. Among the samples with different Au loading content, the one with 1.5 wt% Au (G3) exhibits the highest responses toward toluene and xylene at 340 °C. Moreover, the G3 sensor presents good responses, short response/recovery time, excellent selectivity, good reproducibility, and long-term stability to toluene and xylene. Excellent gas sensing properties of Au-WO3 material make it a good candidate for detecting toluene and xylene. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries have attracted wide attention due to their outstanding properties of high theoretical specific capacity and energy density. However, drawbacks such as the polysulfide shuttle effect have hampered their further practical application. Metal–organic frameworks (MOFs) have stimulated increasing interest in energy storage and conversion. In MOFs, the metal ions can be activated to provide open metal Lewis acid sites to restrain polysulfides. Aiming at sensible solutions, a novel manganese cluster-based MOF equipped with cubic cages, which are walled with abundant open-metal sites (OMSs) obtained from 9-manganese nodes, is used as the cathode host of Li–S batteries. The activated MOF not only provided physical capture and chemical adsorption against polysulfide shuttle but also allowed efficient impregnation of sulfur to facilitate mass transport. Benefiting from these synergetic effects, the composite cathode delivers enhanced electrochemical performance. The battery showed a remaining capacity of about 990 mA h g−1 after 200 cycles at 0.2C and an approximately repeatable rate performance. Significant contribution of the exposed functional metal sites was demonstrated by XPS and SEM of the electrode materials. [ABSTRACT FROM AUTHOR]

In this paper, 17 compounds (1–17) were isolated from the leaves of Hemp (Cannabis sativa f. sativa). Among the isolates, two were determined to be new spirans: cannabispirketal (1), andα-cannabispiranol 4’-O-β-D-glucopyranose (2) by 1D and 2D NMR spectroscopy, LC-MS, and HRESIMS. The known compounds7,8,10,13,15, and16were isolated from Hemp (C. sativa f. sativa) for the first time. Furthermore, compounds8and13were isolated from the nature for the first time. All isolated compounds were evaluated for cytotoxicity on different tissue-derived passage cancer cell lines through cell viability and apoptosis assay. Among these compounds, compounds5,9and16exhibited a broad-spectrum antitumor effect via inhibiting cell proliferation and promoting apoptosis. These results obtained have provided valuable clues to the understanding of the cytotoxic profile for these isolated compounds from Hemp (C. sativa f. sativa). [ABSTRACT FROM PUBLISHER]

A flexible and highly efficient air cathode is fabricated via a simple electro‐deposition approach. This cathode exhibits a series of considerable electrochemical performances, in particular a good cycling performance (more than 70 cycles with the capacity limited 1000 mA h g−1). Based on this flexible cathode, a Li–O2 battery with flexible properties is also assembled, which can power a commercial LED normally. [ABSTRACT FROM AUTHOR]

The pressing demand on the electronic vehicles with long driving range on a single charge has necessitated the development of next-generation high-energy-density batteries. Non-aqueous Li-O2 batteries have received rapidly growing attention due to their higher theoretical energy densities compared to those of state-of-the-art Li-ion batteries.To make them practical for commercial applications, many critical issues must be overcome, including low round-trip efficiency and poor cycling stability, which are intimately connected to the problems resulting from cathode degradation during cycling. Encouragingly, during the past years, much effort has been devoted to enhancing the stability of the cathode using a variety of strategies and these have effectively surmounted the challenges derived from cathode deteriorations,thus endowing Li-O2 batteries with significantly improved electrochemical performances. Here, a brief overview of the general development of Li-O2 battery is presented. Then, critical issues relevant to the cathode instability are discussed and remarkable achievements in enhancing the cathode stability are highlighted. Finally, perspectives towards the development of next generation highly stable cathode are also discussed. [ABSTRACT FROM AUTHOR]

The first concise synthesis of the bidesmosidic oleanolic acid saponins 1- 3 isolated from Fadogia ancylantha (Makoni tea) have been accomplished through a 'one-pot sequential glycosylation' strategy with two glycosyl 1-(trichloroacetimidate)s as glycosyl donors. The synthesized natural products 1- 3 were then evaluated for their inhibitory activities against α-glucosidase, α-amylase, and lipase. Among the assayed compounds 1- 3, compound 1 showed strong α-glucosidase and α-amylase inhibition, with IC50 values of 160 and 180 μ M, respectively. Moreover, compounds 2 and 3 showed strong inhibition against α-glucosidase and lipase, with the respective IC50 values of 170 and 190 μ M, and 190 and 200 μ M. [ABSTRACT FROM AUTHOR]

Cobalt oxide nanosheets (Co[sub 3]O[sub 4] NSs) are grown on carbon paper (CP) by an efficient and facile electrodeposition method. When directly used as free-standing cathode for lithium-oxygen batteries, the Co[sub 3]O[sub 4] NSs/CP is found to be robust and shows enhanced specific capacity and cycling stability. [ABSTRACT FROM AUTHOR]

Chemical synthesis of a trisaccharide related to the cytotoxic triterpenoid saponins isolated from the bark of Albizia procera has been accomplished through a concise stepwise glycosylation strategy starting from commercially available D-xylose, 2-acetamido-2-deoxy- D-glucose and L-arabinose. The target trisaccharide was designed with a 4-methoxyphenyl (MP) aglycone to extend the scope of conversion to suitable glycoconjugates via selective removal of 4-methoxyphenyl (MP) group. An unexpected phenomenon, i.e., the arabinosyl residue assumed the 1 C4 conformation instead of the typical 4 C1 form, was observed. Deprotection could restore the normal conformation. [ABSTRACT FROM AUTHOR]

Ultralong cycle life, high energy, and power density rechargeable lithium-ion batteries are crucial to the ever-increasing large-scale electric energy storage for renewable energy and sustainable road transport. However, the commercial graphite anode cannot perform this challenging task due to its low theoretical capacity and poor rate-capability performance. Metal oxides hold much higher capacity but still are plagued by low rate capability and serious capacity degradation. Here, a novel strategy is developed to prepare binder-free and mechanically robust CoO/graphene electrodes, wherein homogenous and full coating of β-Co(OH)2 nanosheets on graphene, through a novel electrostatic induced spread growth method, plays a key role. The combined advantages of large 2D surface and moderate inflexibility of the as-obtained β-Co(OH)2/graphene hybrid enables its easy coating on Cu foil by a simple layer-by-layer stacking process. Devices made with these electrodes exhibit high rate capability over a temperature range from 0 to 55 °C and, most importantly, maintain excellent cycle stability up to 5000 cycles even at a high current density. [ABSTRACT FROM AUTHOR]

The four hederagenin glycosides 1- 4 were efficiently synthesized through one-pot sequential glycosylations with glycose 1-(trichloroacetimidate)s as donors, resulting in a significantly simplified synthetic procedure without isolation of glycosylation intermediates. The activity of the synthetic hederagenin glycosides 1- 4 against α-glucosidase type IV was evaluated; hederagenin glycoside 4 containing an α- L-rhamnopyranosyl unit showed the best activity with an IC50 value of 47.9 μ M. [ABSTRACT FROM AUTHOR]

Y. Zhang, X.‐B. Zhang, and co‐workers report on page 4345 an electrostatic‐induced spread‐growth method to homogeneously coat CoO on graphene. Binder‐free electrode with excellent structural stability can then be easily prepared by layer‐by‐layer stacking. As an anode for Li‐ion batteries, the asprepared electrode exhibits a high rate capability and excellent cycle stability up to 5000 cycles. This opens up a promising strategy to develop high‐performance anodes for next‐generation LIBs. [ABSTRACT FROM AUTHOR]