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1.
Insights Imaging ; 15(1): 48, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38360968

RESUMO

BACKGROUND: Crohn's disease (CD) is an inflammatory disease of the gastrointestinal tract. The disease behavior changes over time, and endoscopy is crucial in evaluating and monitoring the course of CD. To reduce the economic burden of patients and alleviate the discomfort associated with ineffective examination, it is necessary to fully understand the location, extent, and severity of intestinal stenosis in patients with CD before endoscopy. This study aimed to utilize imaging features of magnetic resonance enterography (MRE) to evaluate intestinal stenosis in patients with CD and to predict whether endoscopy could be passed. METHODS: MRE data of patients with CD were collected, while age, gender, disease duration, and laboratory test parameters were also gathered. Two radiologists analyzed the images and assessed whether endoscopy could be passed based on the imaging performance. Imaging features of MRE were analyzed in groups based on endoscopy results. RESULTS: The readers evaluated the imaging performance for 86 patients to determine if endoscopy could be passed and performed a consistency test (compared between two readers k = 0.812, p = 0.000). In the univariate analysis, statistical differences were observed in the degree of T1WI enhancement, thickness of the intestine wall at the stenosis, and diameter of the upstream intestine between the two groups of whether endoscopy was passed. In multivariate logistic regression, the diameter of the upstream intestine was identified to be an independent factor in predicting whether endoscopy was passed or not (OR = 3.260, p = 0.046). CONCLUSIONS: The utilization of MRE signs for assessing the passage of an endoscope through the narrow segment revealed that the diameter of the upstream intestine emerged as an independent predictor of endoscopic passage. Before performing an endoscopy, MRE can aid in evaluating the passage of the endoscope. CRITICAL RELEVANCE STATEMENT: This retrospective study explored the imaging features of MRE to evaluate intestinal stenosis in patients with Crohn's disease and determined that the diameter of the upstream intestine of the stenotic segment was an independent predictor in assessing endoscopic passage. KEY POINTS: • Endoscopy is crucial in evaluating and monitoring the course of Crohn's disease. • The diameter of the upstream intestine of the stenotic segment was an independent predictor in assessing endoscopic passage. • MRE can aid in evaluating the passage of the endoscope in stenotic segments of Crohn's disease.

2.
Food Res Int ; 177: 113843, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225114

RESUMO

Phosphatidylcholine (PC) oxidation leads to the fusion of nanoliposomes and leakage of containment compounds during the storage period. This study aims to improve the oxidation resistance by partially substituting PC in the osteogenic peptides (OPs) loaded nanoliposomes with hydrogenated phosphatidylcholine (HPC). The investigation assessed the characteristics, stability, and bioaccessibility of these novel nanoliposomes. By altering the PC/HPC mass ratio from 1:0 to 0:1, an increase in the encapsulation efficiency (EE), loading capacity (LC), polydispersity index (PDI), and bioaccessibility of OPs-loaded nanoliposomes was observed. Additionally, there was a decrease in thiobarbituric acid reactive substances (TBARS), peroxide value (POV), non-volatile aldehyde, and ketone. The stability of salt decreased when using HPC alone (0:1). The performance of OPs-loaded nanoliposomes with a PC/HPC mass ratio of 1:3 was found to be satisfactory in terms of storage and pH stability. Fluorescence spectroscopy, Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared spectroscopy (FTIR) revealed a tighter lipid aggregation, enhanced intermolecular van der Waals forces, and hydrogen bond formation in membranes of nanoliposomes containing HPC. The addition of HPC to the nanoliposomes delayed the release of peptides in simulated without affecting osteogenic activity. These results provide guidance for the development of oxidation-resistant nanoliposomes loaded with OPs products.


Assuntos
Lipossomos , Fosfatidilcolinas , Lipossomos/química , Oxirredução , Fosfatidilcolinas/química , Peptídeos
3.
Sci Total Environ ; 904: 166949, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37696408

RESUMO

The treatment of wastewater has become increasingly challenging as a result of its growing complexity. To achieve synergistic removal of coexisting pollutants in wastewater, one promising approach involves the integration of electric fields. We conducted a comprehensive literature review to explore the potential of integrating electric fields and developing efficient electro-intensified simultaneous decontamination systems for wastewater containing coexisting pollutants. The review focused on comprehending the applications and mechanisms of these systems, with a particular emphasis on the deliberate utilization of positive and negative charges. After analyzing the advantages, disadvantages, and application efficacy of these systems, we observed electro-intensified systems exhibit flexible potential through their rational combination, allowing for an expanded range of applications in addressing simultaneous decontamination challenges. Unlike the reviews focusing on single elimination, this work aims to provide guidance in addressing the environmental problems resulting from the coexistence of hazardous contaminants.

4.
Chemistry ; 29(67): e202302304, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37665636

RESUMO

Covalent Organic Frameworks (COFs) are crystalline, porous organic materials. Recent studies have demonstrated novel processing strategies for COFs to form adaptable architectures, but these have focused primarily on imine-linked COFs. This work presents a new synthesis and processing route to produce crystalline hydrazone-linked COF gels and aerogels with hierarchical porosity. The method was implemented to produce a series of hydrazone-linked COFs with different alkyl side-chain substituents, achieving control of the hydrophilicity of the final aerogel. Variation in the length of the alkyl substituents yielded materials with controllable form factors that can preferentially adsorb water or nonpolar organic solvents. Additionally, a method for additive manufacturing of hydrazone-linked COFs using hydroxymethylcellulose as a sacrificial additive is presented. This work demonstrates an effective and simple approach to the fabrication of hydrazone COF aerogels and additive manufacturing to produce hydrazone COFs of desired shape.

5.
ACS Polym Au ; 3(3): 267-275, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37334194

RESUMO

Conjugated polymers offer a number of unique and useful properties for use as battery electrodes, and recent work has reported that conjugated polymers can exhibit excellent rate performance due to electron transport along the polymer backbone. However, the rate performance depends on both ion and electron conduction, and strategies for increasing the intrinsic ionic conductivities of conjugated polymer electrodes are lacking. Here, we investigate a series of conjugated polynapthalene dicarboximide (PNDI) polymers containing oligo(ethylene glycol) (EG) side chains that enhance ion transport. We produced PNDI polymers with varying contents of alkylated and glycolated side chains and investigated the impact on rate performance, specific capacity, cycling stability, and electrochemical properties through a series of charge-discharge, electrochemical impedance spectroscopy, and cyclic voltammetry measurements. We find that the incorporation of glycolated side chains results in electrode materials with exceptional rate performance (up to 500C, 14.4 s per cycle) in thick (up to 20 µm), high-polymer-content (up to 80 wt %) electrodes. Incorporation of EG side chains enhances both ionic and electronic conductivities, and we found that PNDI polymers with at least 90% of NDI units containing EG side chains functioned as carbon-free polymer electrodes. This work demonstrates that polymers with mixed ionic and electronic conduction are excellent candidates for battery electrodes with good cycling stability and capable of ultra-fast rate performance.

6.
Nat Commun ; 14(1): 2865, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208348

RESUMO

Three-dimensional (3D) covalent organic frameworks (COFs) possess higher surface areas, more abundant pore channels, and lower density compared to their two-dimensional counterparts which makes the development of 3D COFs interesting from a fundamental and practical point of view. However, the construction of highly crystalline 3D COF remains challenging. At the same time, the choice of topologies in 3D COFs is limited by the crystallization problem, the lack of availability of suitable building blocks with appropriate reactivity and symmetries, and the difficulties in crystalline structure determination. Herein, we report two highly crystalline 3D COFs with pto and mhq-z topologies designed by rationally selecting rectangular-planar and trigonal-planar building blocks with appropriate conformational strains. The pto 3D COFs show a large pore size of 46 Å with an extremely low calculated density. The mhq-z net topology is solely constructed from totally face-enclosed organic polyhedra displaying a precise uniform micropore size of 1.0 nm. The 3D COFs show a high CO2 adsorption capacity at room temperature and can potentially serve as promising carbon capture adsorbents. This work expands the choice of accessible 3D COF topologies, enriching the structural versatility of COFs.

7.
Nat Nanotechnol ; 18(2): 168-176, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36585515

RESUMO

Cotton textiles are ubiquitous in daily life and are also one of the primary mediums for transmitting viruses and bacteria. Conventional approaches to fabricating antiviral and antibacterial textiles generally load functional additives onto the surface of the fabric and/or their microfibres. However, such modifications are susceptible to deterioration after long-term use due to leaching of the additives. Here we show a different method to impregnate copper ions into the cellulose matrix to form a copper ion-textile (Cu-IT), in which the copper ions strongly coordinate with the oxygen-containing polar functional groups (for example, hydroxyl) of the cellulose chains. The Cu-IT displays high antiviral and antibacterial performance against tobacco mosaic virus and influenza A virus, and Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa and Bacillus subtilis bacteria due to the antimicrobial properties of copper. Furthermore, the strong coordination bonding of copper ions with the hydroxyl functionalities endows the Cu-IT with excellent air/water retainability and superior mechanical stability, which can meet daily use and resist repeated washing. This method to fabricate Cu-IT is cost-effective, ecofriendly and highly scalable, and this textile appears very promising for use in household products, public facilities and medical settings.


Assuntos
Antivirais , Cobre , Têxteis/microbiologia , Antibacterianos , Celulose
8.
Sci Adv ; 8(49): eadd2031, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36490337

RESUMO

Supramolecular frameworks have been widely synthesized for ion transport applications. However, conventional approaches of constructing ion transport pathways in supramolecular frameworks typically require complex processes and display poor scalability, high cost, and limited sustainability. Here, we report the scalable and cost-effective synthesis of an ion-conducting (e.g., Na+) cellulose-derived supramolecule (Na-CS) that features a three-dimensional, hierarchical, and crystalline structure composed of massively aligned, one-dimensional, and ångström-scale open channels. Using wood-based Na-CS as a model material, we achieve high ionic conductivities (e.g., 0.23 S/cm in 20 wt% NaOH at 25 °C) even with a highly dense microstructure, in stark contrast to conventional membranes that typically rely on large pores (e.g., submicrometers to a few micrometers) to obtain comparable ionic conductivities. This synthesis approach can be universally applied to a variety of cellulose materials beyond wood, including cotton textiles, fibers, paper, and ink, which suggests excellent potential for a number of applications such as ion-conductive membranes, ionic cables, and ionotronic devices.

9.
Chem Sci ; 13(33): 9655-9667, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36091887

RESUMO

The sensitivity of covalent organic frameworks (COFs) to pore collapse during activation processes is generally termed activation stability, and activation stability is important for achieving and maintaining COF crystallinity and porosity which are relevant to a variety of applications. However, current understanding of COF stability during activation is insufficient, and prior studies have focused primarily on thermal stability or on the activation stability of other porous materials, such as metal-organic frameworks (MOFs). In this work, we demonstrate and implement a versatile experimental approach to quantify activation stability of COFs and use this to establish a number of relationships between their pore size, the type of pore substituents, pore architecture, and structural robustness. Additionally, density functional theory calculations reveal the impact on both inter-and intra-layer interactions, which govern activation stability, and we demonstrate that activation stability can be systematically tuned using a multivariate synthesis approach involving mixtures of functionalized and unfunctionalized COF building blocks. Our findings provide novel fundamental insights into the activation stability of COFs and offer guidance for the design of more robust COFs.

10.
Front Public Health ; 10: 897386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832274

RESUMO

Environmental pollution liability insurance (EPLI) is a type of insurance purchased by an enterprise to compensate the loss of the victims in the event of an environmental pollution incident. Although EPLI can realize the post-treatment of environmental pollution to a certain extent, there is still less understanding of whether EPLI can improve the environmental performance of enterprises. This study takes A-share listed companies in heavily polluting industries as the research object, determines the treatment group samples according to the Insurance coverage list published by the Ministry of Environmental Protection in 2014 and 2015, and then constructs the empirical test model. In order to ensure that there is no sample selection bias, the PSM method is used to preprocess the samples in this study to ensure the robustness of the conclusions. The empirical tests show that EPLI can significantly improve corporate environmental performance. Further analysis showed that higher public visibility is conducive to the positive environmental effects of EPLI. Compared with state-owned enterprises, non-state-owned enterprises have more significant implementation effects after introducing EPLI. On further examination, the result indicates that environmental pollution liability insurance can improve environmental performance by alleviating corporate financing constraints. The findings of this paper enrich the theory of the economic impact of environmental pollution liability insurance, which has some meaningful theoretical guidance for enterprises and policy makers.


Assuntos
Poluição Ambiental , Seguro de Responsabilidade Civil , China , Conservação dos Recursos Naturais , Indústrias
11.
J Chromatogr Sci ; 60(10): 984-990, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-35662327

RESUMO

Chiral ionic liquids (CILs) have attracted more and more attention due to their superior performance as chiral additives in capillary electrophoresis. In this work, based on the cyclodextrin (CD) derivatives and three new amino acid CILs (trifluoroacetate-L-Hydroxyproline, nitric acid-L-Hydroxyproline and trifluoroacetate-L-threonine), the new synergistic systems were established for chiral drug separation. In contrast to the traditional single glucosyl-ß-CD (Glu-ß-CD) separation system, the CIL/Glu-ß-CD synergistic systems achieved improved resolution of three model drug racemates. Some experimental variables, such as CIL concentration, Glu-ß-CD concentration, buffer pH, applied voltage, and the type and proportion of organic modifier, were optimized in the trifluoroacetate-L-Hydroxyproline/Glu-ß-CD synergistic system. In addition, the recognition process in the synergistic system was studied through the molecular modeling method.


Assuntos
Ciclodextrinas , Líquidos Iônicos , Aminoácidos/química , Eletroforese Capilar/métodos , Concentração de Íons de Hidrogênio , Hidroxiprolina , Líquidos Iônicos/química , Estereoisomerismo , Ácido Trifluoracético
12.
J Pharm Biomed Anal ; 215: 114777, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35462287

RESUMO

Metal organic frameworks (MOFs), as a novel separation mediums, have in recent years attracted wide consideration in capillary electrochromatography (CEC). However, the instability of frameworks limited the application of the MOF-based chiral separation capillary. Herein, Iron-based γ-cyclodextrin metal-organic framework (Fe-CD-MOF) with mesoporous was developed as the chiral stationary phase in open tubular capillary electrochromatography column (OT-CEC) for the stereoisomer separation of fourteen chiral drugs and one chiral alcohol. The capillary column with MOF coating exhibited the best performance (resolution value: 17.07) for anisodamine in any MOF-based capillary column that has never been reported. Moreover, the effect of pH, buffer concentration, and methanol content has been investigated. The novel coated capillary was also applied for the quantitative analysis of a real sample. The Fe-CD-MOF coated capillary showed outstanding repeatability and stability, with the satisfactory relative standard deviations (RSDs) for intra-day, inter-day, and column-to-column. Finally, the enantioseparation mechanism of the Fe-CD-MOF coated capillary was evaluated by adsorption kinetic experiments. In summary, this work indicated the novel and renewable Fe-CD-MOF was a potential chiral stationary phase in CEC chiral separation.


Assuntos
Eletrocromatografia Capilar , Estruturas Metalorgânicas , gama-Ciclodextrinas , Eletrocromatografia Capilar/métodos , Ferro , Estruturas Metalorgânicas/química , Estereoisomerismo
13.
J Am Chem Soc ; 144(13): 5728-5733, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35319193

RESUMO

The connectivity of building units for 3D covalent organic frameworks (COFs) has long been primarily 4 and 6, which have severely curtailed the structural diversity of 3D COFs. Here we demonstrate the successful design and synthesis of a porphyrin based, 8-connected building block with cubic configuration, which could be further reticulated into an unprecedented interpenetrated pcb topology by imine condensation with linear amine monomers. This study presents the first case of high-connectivity building units bearing 8-connected cubic nodes, thus greatly enriching the topological possibilities of 3D COFs.

14.
J Phys Condens Matter ; 34(4)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34474403

RESUMO

Superconducting nanofibers have attracted much attention in basic researches and practical applications due to their unique physical properties such as broad phase transition temperature, excellent heat conductivity, and high critical current density, etc. Electrospinning, as a common method to prepare nanofibers, also has many applications for the preparation of superconducting nanofibers. However, a few of the new methods to fabricate superconducting nanofibers via electrospinning still need further investigations. This review firstly introduces several potential electrospinning methods to obtain superconducting nanofibers, then proceeds to summarize the recent progress in the field of electrospun superconducting materials. The preparation process, difficulties and problems, physical properties of the superconducting nanofibers or nanonetworks (such as superconducting transition temperature, critical current density, critical magnetic field strength, fiber morphology, and structure, etc), theoretical analysis of the properties, and the techniques to improve the performance are also reviewed. In addition, some suggestions and prospects for the development and applications of electrospun superconducting materials in the future are discussed.

15.
Food Funct ; 12(5): 2102-2111, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33564802

RESUMO

The YPRKDETGAERT peptide (PME-1) identified from the Mytilus edulis proteins has been shown to promote the proliferation and differentiation of osteoblasts and it has good bone-forming activity in vitro. Further, PME-1 has been shown to prevent osteoporosis in vivo. PME-1 can be absorbed through the gastrointestinal tract, and the passing rate in monolayer Caco-2 cells was 6.57%. PME-1 can also enter the blood circulation and the concentration of PME-1 in serum reached the maximum, 61.06 ± 26.32 ng mL-1, 20 min after feeding. The multifunctional in vivo imager was used to further determine the distribution of the 5-FITC-(Acp)-YPRKDETGAERT peptide (PME-1-FITC) 2 h after feeding the peptide, and the result confirmed the above results and showed that a part of PME-1-FITC can affect bone in vivo. Therefore, PME-1 not only was easily absorbed in the gastrointestinal tract, but also has the potential beneficial effect on preventing osteoporosis.


Assuntos
Fêmur , Absorção Intestinal/fisiologia , Mytilus edulis/química , Osteoporose , Peptídeos , Animais , Células CACO-2 , Feminino , Fêmur/química , Fêmur/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Ovariectomia , Peptídeos/metabolismo , Peptídeos/farmacocinética , Peptídeos/farmacologia
16.
Nano Lett ; 21(1): 785-790, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356322

RESUMO

The realization of multifunctional nanomaterials is both fundamentally intriguing and practically appealing to be used in nanoscale devices. Here, a heterobilayer consisting of realistic 2D-material components of matching lattice symmetry, that is, one being the ß-phase antimonene ß-Sb known for its strong spin-orbit coupling and ferroelectric In2Se3 monolayer, is designed and explored with first-principles density functional theory. The ferroelectric polarization of the In2Se3 layer induces distinctly different electronic properties in the bilayer. With polarization directed "inward", the bilayer is a trivial insulator with spatially-indirect band gap (potentially beneficial for photovoltaics). Surprisingly, when polarized "outward", the bilayer displays nontrivial topological state, Z2 = 1. This suggests that the external electric field can reversibly switch between these two states, inviting potential applications in future multifunctional devices.

17.
Chem Sci ; 12(48): 16092-16099, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35024131

RESUMO

Covalent organic frameworks (COFs) are crystalline and porous organic materials attractive for photocatalysis applications due to their structural versatility and tunable optical and electronic properties. The use of photocatalysts (PCs) for polymerizations enables the preparation of well-defined polymeric materials under mild reaction conditions. Herein, we report two porphyrin-based donor-acceptor COFs that are effective heterogeneous PCs for photoinduced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT). Using density functional theory (DFT) calculations, we designed porphyrin COFs with strong donor-acceptor characteristics and delocalized conduction bands. The COFs were effective PCs for PET-RAFT, successfully polymerizing a variety of monomers in both organic and aqueous media using visible light (λ max from 460 to 635 nm) to produce polymers with tunable molecular weights (MWs), low molecular weight dispersity, and good chain-end fidelity. The heterogeneous COF PCs could also be reused for PET-RAFT polymerization at least 5 times without losing photocatalytic performance. This work demonstrates porphyrin-based COFs that are effective catalysts for photo-RDRP and establishes design principles for the development of highly active COF PCs for a variety of applications.

18.
ACS Appl Mater Interfaces ; 12(29): 33121-33127, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32602338

RESUMO

Covalent organic frameworks (COFs) are organic, crystalline, highly porous materials attractive for applications such as gas storage, gas separations, catalysis, contaminant adsorption, and membrane filtration. Activation of COFs removes adsorbed solvents and impurities, but common methods for COF activation can result in the collapse of porous structure and loss of accessible surface areas. Here, we present a study of the impact of solvent surface tension on the activation process and demonstrate that activation using the ultralow surface tension solvent perfluorohexane (PFH) is simple and effective for a range of COF materials. We synthesized six different imine-based COFs through imine condensation reactions between tris(4-aminophenyl)benzene (TAPB) or 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (TAPT) and multifunctional di- and tri-benzaldehydes with different aromatic substituents. For each COF, we performed a solvent wash followed by vacuum drying using six solvents varying in surface tension from 11.9 to 72.8 mN m-1. Through powder X-ray diffraction (PXRD) measurements combined with nitrogen adsorption and desorption analysis, we found that some COF chemistries readily lost their porosity during activation with higher surface tension solvents while others were more robust. However, all COFs could be effectively activated using PFH to produce materials with excellent crystallinity and high surface areas, comparable to those for samples activated using supercritical CO2. This work demonstrates that the solvent surface tension used during activation has a strong impact on the potential pore collapse, and activation using PFH provides a simple and effective activation method to produce COFs with excellent crystallinities and pore structures.

19.
J Food Sci Technol ; 57(4): 1301-1309, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32180626

RESUMO

The effects of dynamic ultra-high pressure homogenization (UHPH) on the structure and functional properties of whey protein were investigated in this study. Whey protein solution of 10 mg/mL (1% w/w) was prepared and processed by a laboratory scale high pressure homogenizer with different pressures (25, 50, 100, 150, 200, and 250 MPa) at an initial temperature of 25 °C. Then, the solution samples were evaluated in terms of secondary structure, sulfhydryl and disulfide bond contents, surface hydrophobicity, average particle size, solubility, foaming capacity, emulsifying activity, and thermal properties. It was found that the secondary structure of whey protein changed with the dynamic UHPH treatment. The interchange reaction between the disulfide bond and the sulfhydryl group was promoted and the surface hydrophobicity significantly increased. The functional properties of the whey protein accordingly changed. Specifically, after dynamic UHPH treatment, the average particle size of the whey protein and emulsion decreased while the solubility, the foaming capability and the emulsification stability increased significantly. The results also revealed that with the dynamic UHPH at 150 MPa, the best improvement was observed in the whey protein functional properties. The whey protein solubility increased from 63.15 to 71.61% and the emulsification stability improved from 195 to 467 min.

20.
RSC Adv ; 10(71): 43312-43318, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-35519678

RESUMO

Previous work on the synthesis and preparation of MoO2/graphene nanocomposites (MoO2/G) indicates that MoO2/G is a good anode material for lithium-ion batteries (LIBS). In this work, we used larger super-cells than those used previously to theoretically construct an asymmetric MoO2/G nanocomposite with smaller lattice mismatch. We then calculated the structural, electronic and Li atom diffusion properties of MoO2/G using first-principles calculations based on density functional theory. The results show that asymmetric MoO2/G has metallic properties, good stability and a low Li atom diffusion barrier because of the charge transfer induced by van der Waals interactions. The Li diffusion barriers in the interlayer of MoO2/G are in the range of 0.02-0.29 eV, depending on the relative positions of the Li atom and the MoO2 and the C atoms in the graphene layer. The Li diffusion barriers on the outside layers of the MoO2/G nanocomposite are smaller than those of its pristine materials (MoO2 and graphene). These results are consistent with experimental results. The adsorption of Li atoms in the interlayer of the nanocomposite further promotes the adsorption of Li atoms on the outside sites of the MoO2 layer. Hence, the specific capacity of the MoO2/G nanocomposite is larger than 1682 mA h g-1. These properties all indicate that MoO2/G is a good anode material for LIBS.

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