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Angewandte Chemie (International Ed. in... Jun 2024Layer-stacking behaviors are crucial for two-dimensional covalent organic frameworks (2D COFs) to define their pore structure, physicochemical properties, and functional...
Layer-stacking behaviors are crucial for two-dimensional covalent organic frameworks (2D COFs) to define their pore structure, physicochemical properties, and functional output. So far, fine control over the stacking mode without complex procedures remains a grand challenge. Herein, we proposed a "key-cylinder lock mimic" strategy to synthesize 2D COFs with a tunable layer-stacking mode by taking advantage of ionic liquids (ILs). The staggered (AB) stacking (unlocked) COFs were exclusively obtained by incorporating ILs of symmetric polarity and matching molecular size; otherwise, commonly reported eclipsed (AA) stacking (locked) COFs were observed instead. Mechanistic study revealed that AB stacking was induced by a confined interlocking effect (CIE) brought by anions and bulky cations of the ILs inside pores ("key" and "cylinder", respectively). Excitingly, this strategy can speed up production rate of crystalline powders (e.g., COF-TAPT-Tf@BmimTf2N in merely 30 minutes) under mild reaction conditions. This work highlights the enabling role of ILs to tailor the layer stacking of 2D COFs and promotes further exploration of their stacking mode-dependant applications.
PubMed: 38941108
DOI: 10.1002/anie.202408453 -
Angewandte Chemie (International Ed. in... Jun 2024Near-infrared light-driven photocatalytic CO2 reduction (NIR-CO2PR) holds tremendous promise for the production of valuable commodity chemicals and fuels. However,...
Near-infrared light-driven photocatalytic CO2 reduction (NIR-CO2PR) holds tremendous promise for the production of valuable commodity chemicals and fuels. However, designing photocatalysts capable of reducing CO2 with low energy NIR photons remains challenging. Herein, a novel NIR-driven photocatalyst comprising an anionic Ru complex intercalated between NiAl-layered double hydroxide nanosheets (NiAl-Ru-LDH) is shown to deliver efficient CO2 photoreduction (0.887 μmol h-1) with CO selectivity of 84.81% under 1200 nm illumination and excellent stability over 50 testing cycles. This remarkable performance results from the intercalated Ru complex lowering the LDH band gap (0.98 eV) via a compression-related charge redistribution phenomenon. Furthermore, transient absorption spectroscopy data verified light-induced electron transfer from the Ru complex towards the LDH sheets, increasing the availability of electrons to drive CO2PR. The presence of hydroxyl defects in the LDH sheets promotes the adsorption of CO2 molecules and lowers the energy barriers for NIR-CO2PR to CO. To our knowledge, this is one of the first reports of NIR-CO2PR at wavelengths up to 1200 nm in LDH-based photocatalyst systems.
PubMed: 38941107
DOI: 10.1002/anie.202407638 -
Environmental Geochemistry and Health Jun 2024Iron phosphate-based coating and iron silicate-based coating were used to inhibit the oxidation of sulfide minerals in rainy and submerged environments. The inhibiting...
Iron phosphate-based coating and iron silicate-based coating were used to inhibit the oxidation of sulfide minerals in rainy and submerged environments. The inhibiting effectiveness of coating agents on the oxidation of iron sulfide minerals was investigated using pyrite and rock samples resulting from acid drainage. The film formed with both surface-coating agents was identified by pyrite surface analysis. It was also confirmed that the formation of coatings varies depending on the crystallographic orientation. The inhibitory effects under rainy and submerged conditions were investigated using column experiments. Submerged conditions accelerated deterioration compared to that under rainy conditions. Iron phosphate coating had a significantly better oxidation-inhibitory effect (84.86-98.70%) than iron silicate coating (56.80-92.36%), and at a concentration of 300 mM, H elution was inhibited by more than 90% throughout the experiment. Furthermore, methods for effective film formation were investigated in terms of producing Fe; (1) application of coating agents mixed with oxidant (HO), (2) application of coating agent after the use of the oxidant. In a rainy environment, applying iron phosphate-based coating using the sequential method showed oxidation inhibition effects for cycles 1-9, whereas applying the mixed material showed effects for cycles 9-13. The use of a surface-coating agent after applying an oxidant did not inhibit oxidation. The surface coating agent and the oxidizing agent should be applied as a mixture to form a film.
Topics: Silicates; Iron; Phosphates; Oxidation-Reduction; Acid Rain; Sulfides; Hydrogen Peroxide; Ferric Compounds
PubMed: 38941030
DOI: 10.1007/s10653-024-01996-3 -
Angewandte Chemie (International Ed. in... Jun 2024Sodium-ion batteries (SIBs) have garnered significant interest as one of the most promising energy suppliers for power grid energy storage. However, the poor...
Sodium-ion batteries (SIBs) have garnered significant interest as one of the most promising energy suppliers for power grid energy storage. However, the poor electrode/electrolyte interfacial stability leads to continual electrolyte decomposition and transition metal dissolution, resulting in rapid performance degradation of SIBs. In this work, we propose a strategy integrating multiple functional bonds to regulate electrode/electrolyte interphase by triple-coupling of succinonitrile (SN), sodium hexafluorophosphate (NaPF6) and fluorinated ethylene carbonate (FEC). Theoretical calculation and experiment results show that the solvation structure of Na+ and ClO4- is effectively reconfigured by the solvated FEC, SN and PF6- in PC-based carbonate electrolyte. The newly developed electrolyte demonstrates increased Na+-FEC coordination, weakened interaction of Na+-PC and participation of SN and PF6- anions in solvation, resulting in the formation of a conformal interfacial layer comprising of sodium oxynitrides (NaNxOy), sodium fluoride (NaF) and phosphorus oxide compounds (NaPxOy). Consequently, a 3 Ah pouch full cell of hard carbon//NaNi1/3Fe1/3Mn1/3O2 exhibits an excellent capacity retention of 90.4% after 1000 cycles. Detailed postmortem analysis of interface chemistry is further illustrated by multiple characterization methods. This study provides a new avenue for developing electrolyte formulations with multiple functional bonds integrated interphases to significantly improve the long-term cycling stability of SIBs.
PubMed: 38940896
DOI: 10.1002/anie.202406277 -
Plant Foods For Human Nutrition... Jun 2024Jack bean (JB), Canavalia ensiformis (L.) DC, is a commonly cultivated legume in Indonesia. It is rich in protein, which can be hydrolyzed, making it potentially a good...
Jack bean (JB), Canavalia ensiformis (L.) DC, is a commonly cultivated legume in Indonesia. It is rich in protein, which can be hydrolyzed, making it potentially a good source of bioactive peptides. Intestinal inflammation is associated with several diseases, and the production of interleukin-8 (IL-8) in intestinal epithelial cells induced by tumor necrosis factor (TNF)-α has an important role in inflammatory reaction. The present study investigated the anti-inflammatory effects of peptides generated from enzymatic hydrolysis of JB protein on human intestinal Caco-2BBe cells. Additionally, in silico approaches were used to identify potential bioactive peptides. JB protein hydrolysate (JBPH) prepared using pepsin and pancreatin reduced the IL-8 expression at protein and mRNA levels in Caco-2BBe cells stimulated with TNF-α. Immunoblot analysis showed that the JBPH reduced the TNF-α-induced phosphorylation of c-Jun-NH(2)-terminal kinase, nuclear factor kappa B (NF-κB), and p38 proteins. Anti-inflammatory activity was observed in the 30% acetonitrile fraction of JBPH separated on a Sep-Pak C18 column. An ultrafiltration method revealed that relatively small peptides (< 3 kDa) had a potent inhibitory effect on the IL-8 production. Purification of the peptides by reversed-phase and anion-exchange high performance chromatography produced three peptide fractions with anti-inflammatory activities. A combination of mass spectrometry analysis and in silico approaches identified the potential anti-inflammatory peptides. Peptides derived from JB protein reduces the TNF-α-induced inflammatory response in Caco-2BBe cells via NF-κB and mitogen-activated protein kinase signaling pathways. Our results may lead to a novel therapeutic approach to promote intestinal health.
PubMed: 38940894
DOI: 10.1007/s11130-024-01201-x -
Current Microbiology Jun 2024Garlic (Allium sativum L.), particularly its volatile essential oil, is widely recognized for medicinal properties. We have evaluated the efficacy of Indian Garlic...
Garlic (Allium sativum L.), particularly its volatile essential oil, is widely recognized for medicinal properties. We have evaluated the efficacy of Indian Garlic Essential Oil (GEO) for antimicrobial and antibiofilm activity and its bioactive constituents. Allyl sulfur-rich compounds were identified as predominant phytochemicals in GEO, constituting 96.51% of total volatile oils, with 38% Diallyl trisulphide (DTS) as most abundant. GEO exhibited significant antibacterial activity against eleven bacteria, including three drug-resistant strains with minimum inhibitory concentrations (MICs) ranging from 78 to 1250 µg/mL. In bacterial growth kinetic assay GEO effectively inhibited growth of all tested strains at its ½ MIC. Antibiofilm activity was evident against two important human pathogens, S. aureus and P. aeruginosa. Mechanistic studies demonstrated that GEO disrupts bacterial cell membranes, leading to the release of nucleic acids, proteins, and reactive oxygen species. Additionally, GEO demonstrated potent antioxidant activity at IC 31.18 mg/mL, while its isolated constituents, Diallyl disulphide (DDS) and Diallyl trisulphide (DTS), showed effective antibacterial activity ranging from 125 to 500 µg/mL and 250-1000 µg/mL respectively. Overall, GEO displayed promising antimicrobial and antibiofilm activity against enteric bacteria, suggesting its potential application in the food industry.
Topics: Garlic; Oils, Volatile; Antioxidants; Anti-Bacterial Agents; Biofilms; Microbial Sensitivity Tests; Staphylococcus aureus; Allyl Compounds; Phytochemicals; Sulfides; Bacteria; Pseudomonas aeruginosa; Disulfides; India; Plant Oils; Humans; Plant Extracts
PubMed: 38940852
DOI: 10.1007/s00284-024-03753-2 -
Physical Chemistry Chemical Physics :... Jun 2024The aggregation of halide atoms into gold clusters offers an interesting scenario for the development of novel metal-based cavities for anion recognition and sensing...
On the halide aggregation into the [Au(PPh)] cluster core. Insights from structural, optical and interaction energy analysis in [(PhPAu)X] and [(PhPAu)X] species (X = Cl, Br, I).
The aggregation of halide atoms into gold clusters offers an interesting scenario for the development of novel metal-based cavities for anion recognition and sensing applications. Thus, further understanding of the different contributing terms leading to efficient cluster-halide aggregation is relevant to guide their synthetic design. In this report, we evaluate the formation of [(PhPAu)X] and [(PhPAu)X] species (X = Cl, Br, I) in terms of different energy contributions underlying the stabilization of the cluster-halide interaction, and the expected UV-vis absorption profiles as a result of the variation in frontier orbital arrangements. Our results denote that a non-planar Au core shape enables enhanced halide aggregation, which is similar for Cl, Br, and I, in comparison to the hypothetical planar Au counterparts. The electrostatic nature of the interaction involves a decreasing ion-dipole term along with the series, and for iodine species, higher-order electrostatic contributions become more relevant. Hence, the obtained results help in gaining further understanding of the different stabilizing and destabilizing contributions to suitable cluster-based cavities for the incorporation of different monoatomic anions.
PubMed: 38940752
DOI: 10.1039/d4cp01467g -
The Journal of Organic Chemistry Jun 2024Herein, a photocatalytic umpolung strategy for reductive carboxylation of imines for the synthesis of α-amino acids was disclosed. Carbon dioxide radical anion (CO)...
Herein, a photocatalytic umpolung strategy for reductive carboxylation of imines for the synthesis of α-amino acids was disclosed. Carbon dioxide radical anion (CO) generated from formate is the key single electron reductant in the reactions. An unprecedentedly broad substrate scope of imines with excellent reaction yields was obtained with carbon dioxide (CO) and formate salt as carbon sources.
PubMed: 38940722
DOI: 10.1021/acs.joc.3c02887 -
Inorganic Chemistry Jun 2024Binary metal hydrides can act as low-temperature reducing agents for complex oxides in the solid state, facilitating the synthesis of anion-deficient oxide or oxyhydride...
Binary metal hydrides can act as low-temperature reducing agents for complex oxides in the solid state, facilitating the synthesis of anion-deficient oxide or oxyhydride phases. The reaction of LaSrCoRuO, with CaH in a sealed tube yields the face-centered cubic phase LaSrCoRuOH. The reaction with LiH under similar conditions converts LaSrCoRuO to a mixture of tetragonal LaSrCoRuOH and cubic LaSrCoRuOH. The formation of the LaSrCoRuOH oxyhydride phases proceeds directly from the parent oxide, with no evidence for anion-deficient LaSrCoRuO intermediates, in contrast with many other topochemically synthesized transition-metal oxyhydrides. However, the reaction between LaSrCoRuO and LiH under flowing argon yields a mixture of LaSrCoRuO and the infinite layer phase LaSrCoRuO. The change to all-oxide products when reactions are performed under flowing argon is attributed to the lower hydrogen partial pressure under these conditions. The implications for the reaction mechanism of these topochemical transformations is discussed along with the role of the hydrogen partial pressure in oxyhydride synthesis. Magnetization measurements indicate the LaSrCoRuOH phases exhibit local moments on Co and Ru centers, which are coupled antiferromagnetically. In contrast, LaSrCoRuO exhibits ferromagnetic behavior with a Curie temperature above 350 K, which can be rationalized on the basis of superexchange coupling between the Co and Ru centers.
PubMed: 38940638
DOI: 10.1021/acs.inorgchem.4c01568 -
Small (Weinheim An Der Bergstrasse,... Jun 2024The synthesis, crystal structure and room-temperature phosphorescence (RTP) of a 2D metal-free inorganic covalent framework ((Hen) [BO(OH)], named as CityU-12, and en...
The synthesis, crystal structure and room-temperature phosphorescence (RTP) of a 2D metal-free inorganic covalent framework ((Hen) [BO(OH)], named as CityU-12, and en represents for ethylenediamine) are reported. The precise structure information of CityU-12 has been disclosed through both single-crystal X-ray diffraction (SCXRD) analysis and low-dose high-resolution transmission electron microscopy (LD-HRTEM) study. The SCXRD results show that CityU-12 composes of 2D anionic B─O-based covalent inorganic frameworks with protonated ethylenediamine locating in the pore sites of 2D B─O layers while LD-HRTEM suggests that CityU-12 has an interplanar distance of 0.60 nm for (00 ) crystal plane and 0.60 nm for (10 ) crystal plane. The optical studies show that CityU-12 is an excellent nonconventional RTP material with the emission peak at 530 nm and a lifetime of 1.5 s. The quantum yield is 84.6% and the afterglow time is as long as 2.5 s. This work demonstrates that metal-free B─O frameworks can be promising nonconventional phosphors for RTP.
PubMed: 38940500
DOI: 10.1002/smll.202404129