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1.
RSC Adv ; 14(29): 20536-20542, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38952945

RESUMEN

Phytochemical studies on Aphanamixis plants have attracted considerable attention over the past few decades due to the structural diversities and significant biological activities of terpenoids produced by these plants. In the present study, five new acyclic diterpene lactone derivatives, aphanamixionolides A-E (1-5), and three known tirucallane-type triterpenes, namely, piscidinol A (6), hispidone (7), and bourjotinolone A (8), were isolated from the leaves of Aphanamixis polystachya. Their structures were elucidated by comprehensive analyses of HR-ESI-MS and NMR spectroscopic data and by comparison with those reported in the literature. Absolute configurations of the new compounds were determined by experimental and TD-DFT calculated ECD spectra. Compounds 1-8 inhibited NO production with IC50 values of 10.2-37.7 µM, which are comparable to positive control l-NMMA (IC50: 31.5 µM).

2.
Dermatol Reports ; 16(2): 9868, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38957630

RESUMEN

Pemphigus is a rare blistering autoimmune disease that damages the integumentary system and lowers the quality of life of patients. Interleukin-6 (IL-6) has been linked to the immunopathogenesis of pemphigus, according to recent research. Thus, the investigation purpose was to assess the function of IL-6 in the development and intensity of pemphigus disease. Between January 2022 and August 2022, a case-series study involving 26 patients with pemphigus vulgaris (PV), four patients with pemphigus foliaceus (PF), and 20 healthy volunteers was carried out at the Ho Chi Minh City Hospital of Dermato-Venereology. Patients with PV and PF had significantly higher serum IL-6 concentrations than healthy volunteers (p<0.001). Patients with a positive Nikolsky sign had significantly higher serum IL-6 concentrations than those with a negative sign (p<0.001). The serum IL-6 concentration and the pemphigus disease area index were found to significantly correlate (r=0.8, p<0.001). According to our findings, IL-6 might be a significant factor in pemphigus development and severity. Thus, novel treatments that specifically target IL-6 could be a good option for managing pemphigus, particularly in its more severe forms.

3.
Chem Biodivers ; : e202401273, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38828879

RESUMEN

Eight furostanol glycosides including five undescribed compounds, named tribufurostanosides A-E (1-5), and three known ones (6-8) were isolated from the fruits of Tribulus terrestris L. Their chemical structures were determined by the IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Furostanols 1-8 significantly inhibited nitric oxide production in LPS activated RAW 264.7 cells with IC50 values ranging from 14.2 to 64.7 µM, compared to that of the positive control compound, dexamethazone (IC50 13.6 µM).

4.
Front Psychiatry ; 15: 1400128, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938466

RESUMEN

Objective: This study aimed to measure depression among children and adolescents during the COVID-19 pandemic in Hanoi, Vietnam and its associated factors by using the Short Mood and Feelings Questionnaire (SMFQ) instrument. Methods: We conducted a cross-sectional study among students from grades 6 to 9 within two secondary schools in Hanoi, the capital of Vietnam. A structured questionnaire was used, including information about personal characteristics, perception of COVID-19, and SMFQ. Factor analysis, Multivariate logistic and Tobit regression models were used. Results: Among 2378 students, 8.8% had depressive symptoms. The mean SMFQ score was 4.5 (SD=5.0). Being female, studying in higher grades, perceived low household income, higher perceived impacts of COVID-19 on health and higher perceived impacts of COVID-19-related quarantine on life were positively associated with factors' scores, SMFQ score and depressive symptoms. Meanwhile, having better academic performance, living with parents and having higher perceived knowledge about COVID-19 were negatively associated with factors scores, SMFQ score and depressive symptoms. Conclusions: Depressive symptoms were common among secondary school students in Hanoi, Vietnam, during the COVID-19 pandemic. Tailored interventions to improve pandemic-related knowledge and family and school support should be warranted for the students to enhance their mental well-being.

5.
J Nat Med ; 78(3): 741-752, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38573418

RESUMEN

In this study, nine triterpene glycosides including seven previously undescribed compounds (1-7), were isolated from leaves of Cryptolepis buchananii R.Br. ex Roem. and Schult. using various chromatographic methods. The chemical structures of the compounds were elucidated to be 3-O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranosyluncargenin C 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (1), 3-O-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranosyluncargenin C 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (2), 3-O-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranosyluncargenin C 28-O-ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (3), 3-O-ß-D-glucopyranosyl-(1 → 2)-ß-D-glucopyranosylhederagenin 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (4), 3-O-ß-D-glucopyranosylarjunolic acid 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (5), 3-O-ß-D-glucopyranosyl-(1 → 2)-ß- D-glucopyranosyl-6ß,23-dihydroxyursolic acid 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (6), 3-O-ß-D-glucopyranosyl-6ß,23-dihydroxyursolic acid 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (7), asiatic acid 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (8), and 3-O-ß-D-glucopyranosylasiatic acid 28-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl ester (9), through infrared, high-resolution electrospray ionization mass spectrometry, one- and two-dimensional nuclear magnetic resonance spectral analyses. The isolates inhibited nitric oxide production in lipopolysaccharide-activated RAW 264.7 cells, with half-maximal inhibitory concentration (IC50) values of 18.8-58.5 µM, compared to the positive control compound, dexamethasone, which exhibited an IC50 of 14.1 µM.


Asunto(s)
Glicósidos , Óxido Nítrico , Hojas de la Planta , Triterpenos , Triterpenos/química , Triterpenos/farmacología , Triterpenos/aislamiento & purificación , Óxido Nítrico/metabolismo , Glicósidos/química , Glicósidos/farmacología , Glicósidos/aislamiento & purificación , Ratones , Animales , Estructura Molecular , Hojas de la Planta/química , Células RAW 264.7 , Extractos Vegetales/química , Extractos Vegetales/farmacología
6.
RSC Adv ; 14(17): 12147-12157, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38628471

RESUMEN

In this study, seven new pentacyclic triterpene glycosides, named dendrocinaosides A-G (1-7), and six known ones (8-13) were isolated from the whole plants of Dendrobium officinale. Their structures were determined by analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1-4, 8, and 9 potentially inhibited α-glucosidase and α-amylase activities with the IC50 values ranging from 31.3 ± 2.2 to 42.4 ± 2.5 µM for anti α-glucosidase and from 36.5 ± 1.8 to 56.4 ± 2.0 µM for anti α-amylase activities, respectively, which were lower than that of the positive control, acarbose, showing IC50 values of 47.1 ± 1.4 µM for anti α-glucosidase and 145.7 ± 2.2 µM for anti α-amylase.

7.
Prog Mol Biol Transl Sci ; 204: 163-176, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38458737

RESUMEN

It is estimated that millions of people around the world experience various types of tissue injuries every year. Regenerative medicine was born and developed for understanding and application with the aim of replacing affected organs or some cells. The research, manufacture, production, and distribution of RNA in cells have acted as a basic foundation for the development and testing of therapies and treatments that are widely applied in different fields of medicine. Vaccines against COVID-19 are considered one of the brilliant and outstanding successes of RNA therapeutics research. With the characteristics of bio-derived RNA therapeutics, the mechanism of rapid implementation, safe production, and flexibility to create proteins depending on actual requirements. Based on the advantages above in this review, we discuss RNA therapeutics for regenerative medicine, and the types of RNA therapies currently being used for regenerative medicine. The relationship between disease and regenerative medicine is currently being studied or tested in RNA therapeutics. We have also covered the mechanisms of action of RNA therapy for regenerative medicine and some of the limitations in our current understanding of the effects of RNA therapy in this area. Additionally, we have also covered developing RNA therapeutics for regenerative medicine, focusing on RNA therapeutics for regenerative medicine. As a final point, we discuss potential applications for therapeutics for regenerative medicine in the future, as well as their mechanisms.


Asunto(s)
ARN , Medicina Regenerativa , Humanos , ARN/uso terapéutico , Vacunas contra la COVID-19
8.
Front Public Health ; 12: 1232856, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435293

RESUMEN

Introduction: The objective of the current study was to examine the rate of high school students at risk of anxiety disorder during the COVID-19 pandemic in Vietnam, as well as the coping strategies utilized within this demographic. Methods: An evaluation was conducted through the utilization of mixed methods, consisting of a combination of a cross-sectional study and in-depth interviews. In this study, a sample of 3,910 students from 13 high schools in Hanoi, Vietnam were selected for participation. The measurement of symptoms of anxiety disorder was conducted through the application of the seven-item General Anxiety Disorder (GAD-7) scale. To comprehend the underlying causes of anxiety and the various coping mechanisms employed, in-depth interviews were conducted. Results: The findings indicate a prevalence rate of anxiety disorder symptoms among students at 40.6% The prevalence rates of mild, moderate, and severe anxiety symptoms were found to be 23.9%, 10.9%, and 5.8%, respectively. In-depth interviews uncovered multiple sources of anxiety experienced by high school students, namely their academic performance, social interactions, prejudicial attitudes from their social circle, and familial expectations. Numerous coping strategies were then documented. Discussion: The current investigation ascertained that there exists a moderate level of anxiety amongst high school students in Hanoi, Vietnam during the COVID-19 outbreak. Furthermore, this study configured potential indicators to identify vulnerable individuals and further suggests the development of targeted interventions.


Asunto(s)
Trastornos de Ansiedad , COVID-19 , Habilidades de Afrontamiento , Humanos , Vietnam/epidemiología , Estudios Transversales , Pandemias , COVID-19/epidemiología , Ansiedad/epidemiología , Estudiantes
9.
Fitoterapia ; 175: 105903, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38479620

RESUMEN

A phytochemical study of the aerial parts of Piper mutabile C. DC. revealed seven undescribed compounds [two (2-7')-neolignans and five polyoxygenated cyclohexene glycosides] and six known propenylcatechol derivatives. The chemical structures of the isolated compounds were elucidated by extensive HR-ESI-MS and NMR analyses, as well as comparison with the literature. The absolute configurations of the (2-7')-neolignans were confirmed by GIAO 13C NMR calculations with a sorted training set strategy and TD-DFT calculation ECD spectra. The (2-7')-neolignans and polyoxygenated cyclohexene glycosides are unusual in natural sources. Undescribed neolignans 1 and 2 inhibited NO production in RAW 264.7 cells, with respective IC50 values of 14.4 and 9.5 µM.


Asunto(s)
Ciclohexenos , Glicósidos , Lignanos , Óxido Nítrico , Fitoquímicos , Piper , Componentes Aéreos de las Plantas , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Células RAW 264.7 , Ratones , Piper/química , Estructura Molecular , Componentes Aéreos de las Plantas/química , Animales , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Lignanos/farmacología , Lignanos/aislamiento & purificación , Lignanos/química , Glicósidos/farmacología , Glicósidos/aislamiento & purificación , Glicósidos/química , Ciclohexenos/farmacología , Ciclohexenos/aislamiento & purificación , China
10.
Prog Mol Biol Transl Sci ; 203: 273-286, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38360003

RESUMEN

Blood disorders are defined as diseases related to the structure, function, and formation of blood cells. These diseases lead to increased years of life loss, reduced quality of life, and increased financial burden for social security systems around the world. Common blood disorder treatments such as using chemical drugs, organ transplants, or stem cell therapy have not yet approached the best goals, and treatment costs are also very high. RNA with a research history dating back several decades has emerged as a potential method to treat hematological diseases. A number of clinical trials have been conducted to pave the way for the use of RNA molecules to cure blood disorders. This novel approach takes advantage of regulatory mechanisms and the versatility of RNA-based oligonucleotides to target genes and cellular pathways involved in the pathogenesis of specific diseases. Despite positive results, currently, there is no RNA drug to treat blood-related diseases approved or marketed. Before the clinical adoption of RNA-based therapies, challenges such as safe delivery of RNA molecules to the target site and off-target effects of injected RNA in the body need to be addressed. In brief, RNA-based therapies open novel avenues for the treatment of hematological diseases, and clinical trials for approval and practical use of RNA-targeted are crucial.


Asunto(s)
Enfermedades Hematológicas , ARN , Humanos , ARN/uso terapéutico , Calidad de Vida , Sistemas de Liberación de Medicamentos/métodos , Enfermedades Hematológicas/genética , Enfermedades Hematológicas/terapia
11.
Proc Natl Acad Sci U S A ; 121(4): e2311732121, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38232289

RESUMEN

Rechargeable lithium (Li) metal batteries face challenges in achieving stable cycling due to the instability of the solid electrolyte interphase (SEI). The Li-ion solvation structure and its desolvation process are crucial for the formation of a stable SEI on Li metal anodes and improving Li plating/stripping kinetics. This research introduces an interfacial desolvation coating technique to actively modulate the Li-ion solvation structure at the Li metal interface and regulate the participation of the electrolyte solvent in SEI formation. Through experimental investigations conducted using a carbonate electrolyte with limited compatibility to Li metal, the optimized desolvation coating layer, composed of 12-crown-4 ether-modified silica materials, selectively displaces strongly coordinating solvents while simultaneously enriching weakly coordinating fluorinated solvents at the Li metal/electrolyte interface. This selective desolvation and enrichment effect reduce solvent participation to SEI and thus facilitate the formation of a LiF-dominant SEI with greatly reduced organic species on the Li metal surface, as conclusively verified through various characterization techniques including XPS, quantitative NMR, operando NMR, cryo-TEM, EELS, and EDS. The interfacial desolvation coating technique enables excellent rate cycling stability (i.e., 1C) of the Li metal anode and prolonged cycling life of the Li||LiCoO2 pouch cell in the conventional carbonate electrolyte (E/C 2.6 g/Ah), with 80% capacity retention after 333 cycles.

12.
Adv Sci (Weinh) ; 11(13): e2308813, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38268161

RESUMEN

Rare-earth complexes are vital for separation chemistry and useful in many advanced applications including emission and energy upconversion. Here, 2D rare-earth clusters having net charges are formed on a metal surface, enabling investigations of their structural and electronic properties on a one-cluster-at-a-time basis using scanning tunneling microscopy. While these ionic complexes are highly mobile on the surface at ≈100 K, their mobility is greatly reduced at 5 K and reveals stable and self-limiting clusters. In each cluster, a pair of charged rare-earth complexes formed by electrostatic and dispersive interactions act as a basic unit, and the clusters are chiral. Unlike other non-ionic molecular clusters formed on the surfaces, these rare-earth clusters show mechanical stability. Moreover, their high mobility on the surface suggests that they are in a 2D liquid-like state.

13.
Phytochemistry ; 220: 113997, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38244960

RESUMEN

Aphanapolystachones A-C (1-3), three undescribed sesquiterpene-diterpene heterodimers, were obtained from the fruits of Aphanamixis polystachya. Their structures and absolute configurations were identified by extensive analysis of HR-ESI-MS, NMR, experimental and TD-DFT calculated ECD spectra. The biosynthetic pathway of them was also proposed, which is produced by key intermolecular Diels-Alder [4 + 2]-cycloaddition reaction between a guaiane sesquiterpene and an acyclic diterpene. Compounds 1-3 inhibited NO production in LPS activated RAW 264.7 cells with the IC50 values of 1.7 ± 0.2, 3.0 ± 0.3, 5.3 ± 0.3 µM, respectively, lower than that of the positive control L-NMMA (31.5 ± 2.6 µM). In addition, compounds 1-3 significantly reduced IL-6 secretion at diluted concentration of 0.4 µM.


Asunto(s)
Diterpenos , Meliaceae , Sesquiterpenos , Animales , Ratones , Células RAW 264.7 , Frutas/química , Espectroscopía de Resonancia Magnética , Meliaceae/química , Diterpenos/química , Sesquiterpenos/farmacología , Sesquiterpenos/análisis , Estructura Molecular
14.
Chem Biodivers ; 21(3): e202302105, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38269614

RESUMEN

Four previously undescribed compounds named phyllancosides A and B (1 and 2), and phyllancochines A and B (3 and 4) together with ten known compounds (5-14) were isolated from the aerial parts of Phyllanthus cochinchinensis Spreng. Their chemical structures were elucidated on the basis of comprehensive analysis of IR, HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) spectra. Compounds 3, 4, and 10 showed antimicrobial activity against E. faecalis, S. aureus, and B. cereus with the MIC values in range of 32-256 µg/mL. Compound 11 inhibited E. faecalis and B. cereus, and 7 inhibited S. aureus with the MIC values in range of 64-128 µg/mL. In addition, compounds 1, 3, 4, 8, and 9 showed significantly NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values ranging from 36.57 to 56.34 µM.


Asunto(s)
Antiinfecciosos , Lipopolisacáridos , Animales , Ratones , Células RAW 264.7 , Estructura Molecular , Lipopolisacáridos/farmacología , Staphylococcus aureus , Óxido Nítrico , Componentes Aéreos de las Plantas/química , Antiinfecciosos/análisis
15.
Chem Biodivers ; 21(3): e202400124, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38279623

RESUMEN

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.


Asunto(s)
Syzygium , Triterpenos , Syzygium/química , alfa-Glucosidasas , Extractos Vegetales/farmacología , Triterpenos/farmacología , alfa-Amilasas , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química
16.
Nat Prod Res ; 38(5): 759-767, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37005002

RESUMEN

Four new glycosides, named amplexicosides A-D (1-4), and five known compounds: benzyl 2-[ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyloxy]-benzoate (5), benzyl 2-neohesperidosyloxy-6-hydroxybenzoate (6), chrysandroside A (7), chrysandroside B (8) and camelliquercetiside C (9) were isolated from the branches and leaves of Camellia amplexicaulis (Pit.) Cohen-Stuart. Their structures were elucidated using HR-ESI-MS and 1D- and 2D-NMR spectra and compared to reported NMR data. All of the isolated compounds were screened in an α-glucosidase assay. Compounds 4, 8, and 9 significantly inhibited α-glucosidase with respective IC50 values of 254.9 ± 4.2, 304.8 ± 11.9 and 228.1 ± 16.4 µM.


Asunto(s)
Camellia , Glicósidos Cardíacos , Glicósidos/farmacología , Glicósidos/química , alfa-Glucosidasas , Estructura Molecular , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química
17.
Chem Biodivers ; 21(2): e202301764, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38050750

RESUMEN

Dracaena cambodiana Pierre ex Gagnep. is well known as a medicinal plant and widely distributed in Vietnam. Phytochemical investigation on the trunks of D. cambodiana lead to the isolation of four undescribed compounds (1-4) together with seven known ones (5-11). Their structures were determined to be pennogenin-24-yl-O-ß-D-glucopyranoside (1), 17α-hydroxycambodianoside C (2), (25R)-27-hydroxypenogenin 3-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (3), (3ß,25R)-17α,22α-dihydroxy-furost-5-en-3-yl-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (4), dracagenin A (5), 1-O-ß-D-glucopyranosyl-2-hydroxy-4-allylbenzene (6), 1-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-2-hydroxy-allylbenzene (7), 2-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-1-hydroxy-allylbenzene (8), cinnamrutinoside A (9), icariside D1 (10), and seco-isolariciresinol 9-O-ß-glucopyranoside (11) by extensive spectroscopic investigation, HR-ESI-MS, 1D and 2D NMR spectra. The anti-inflammatory activity of the isolated compounds was evaluated on macrophages. Compounds 1-6 significantly inhibited nitric oxide production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Among them, compound 1 showed the best inhibitory activity with an IC50 value of 8.90±0.56 µM.


Asunto(s)
Derivados de Alilbenceno , Dracaena , Saponinas , Lipopolisacáridos/farmacología , Estructura Molecular , Óxido Nítrico , Saponinas/farmacología , Saponinas/química , Glucósidos/química , Glucósidos/farmacología
18.
Faraday Discuss ; 248(0): 134-144, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-37791894

RESUMEN

There is much interest in developing new energy storage systems to replace currently available ones that mainly work based on Li-ion intercalations. One attractive area is the Li-air battery for which most of the research has involved liquid electrolytes. There have been few studies on the use of a solid electrolyte in a Li-air battery. Recently, we reported the successful use of a solid-state electrolyte in a Li-air battery resulting in a Li2O product and potentially much higher energy density than in a Li-air battery based on either a Li2O2 or LiO2 product (Science, 2023, 379, 499). In this paper we discuss how the discharge mechanism involved in this solid-state Li-air battery differs from that of a Li-air battery with a liquid electrolyte. The solid-state mechanism is further explored with density functional studies of various interfaces involving the discharge product. We discuss the relevance of the results to the discharge mechanism in the solid-state Li-air battery.

19.
Adv Mater ; 36(7): e2306462, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38013502

RESUMEN

Anion solvation in electrolytes can largely change the electrochemical performance of the electrolytes, yet has been rarely investigated. Herein, three anions of bis(trifluoromethanesulfonyl)imide (TFSI), bis(fluorosulfonyl)imide (FSI), and derived asymmetric (fluorosulfonyl)(trifluoro-methanesulfonyl)imide (FTFSI) are systematically examined in a weakly Li+ cation solvating solvent of bis(3-fluoropropyl)ether (BFPE). In-situ liquid secondary ion mass spectrometry demonstrates that FTFSI- and FSI- anions are associated with BFPE solvent, while weak TFSI- /BFPE cluster signals are detected. Molecular modeling further reveals that the anion-solvent interaction is accompanied by the formation of H-bonding-like interactions. Anion solvation enhances the Li+ cation transfer number and reduces the organic component in solid electrolyte interphase, which enhances the Li plating/stripping Coulombic efficiency at a low temperature of -30 °C from 42.4% in TFSI-based electrolytes to 98.7% in 1.5 m LiFTFSI and 97.9% in LiFSI-BFPE electrolytes. The anion-solvent interactions, especially asymmetric anion solvation also accelerate the Li+ desolvation kinetics. The 1.5 m LiFTFSI-BFPE electrolyte with strong anion-solvent interaction enables LiNi0.8 Mn0.1 Co0.1 O2 (NMC811)||Li (20 µm) full cell with stable cyclability even under -40 °C, retaining over 92% of initial capacity (115 mAh g-1 , after 100 cycles). The anion-solvent interactions insights allow to rational design the electrolyte for lithium metal batteries and beyond to achieve high performance.

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