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1.
Front Microbiol ; 15: 1362487, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808274

RESUMO

Endoplasmic reticulum (ER) stress is related to oxidative stress (OS) and leads to intestinal injury. Bacillus amyloliquefaciens SC06 (SC06) can regulate OS, but its roles in intestinal ER stress remains unclear. Using a 2 × 2 factorial design, 32 weaned piglets were treated by two SC06 levels (0 or 1 × 108 CFU/g), either with or without diquat (DQ) injection. We found that SC06 increased growth performance, decreased ileal permeability, OS and ER stress in DQ-treated piglets. Transcriptome showed that differentially expressed genes (DEGs) induced by DQ were enriched in NF-κB signaling pathway. DEGs between DQ- and SC06 + DQ-treated piglets were enriched in glutathione metabolism pathway. Ileal microbiome revealed that the SC06 + DQ treatment decreased Clostridium and increased Actinobacillus. Correlations were found between microbiota and ER stress genes. In conclusion, dietary SC06 supplementation increased the performance, decreased the permeability, OS and ER stress in weaned piglets by regulating ileal genes and microbiota.

2.
Front Public Health ; 12: 1258188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444439

RESUMO

Introduction: In the response to and prevention and control of the Novel coronavirus pneumonia, the COVID-19 vaccine does not provide lifelong immunity, and it is therefore important to increase the rate of booster shots of the COVID-19 vaccine. In the field of information health science, research has found that information frames have an impact in changing individual attitudes and health behaviors. Objective: This study focuses on the effects of different influencing factors on the public's willingness to receive the booster shots of the COVID-19 vaccine under two information frameworks. Methods: An online questionnaire was conducted to explore the effects of demographic characteristics, personal awareness, social relationships, risk disclosure, perceived booster vaccination protection rate, and duration of protection under the assumption of an information framework. T test and one-way analysis were used to testing the effect of variables. Results: (1) The persuasion effect under the gain frame is higher than that under the loss frame (B = 0.863 vs. B = 0.746); (2) There was no significant difference in subjects' intention of booster vaccination in terms of gender, age, income, occupation, educational background and place of residence. Whether family members received booster vaccination was strongly correlated with their intention of vaccination under the loss framework (p = 0.017, M = 4.63, SD = 0.664). (3) The higher the understanding of COVID-19, the higher the degree of compliance with the government's COVID-19 prevention and control measures, and the higher the willingness to strengthen vaccination; (4) Risk disclosure has a significant impact on people's willingness to receive COVID-19 booster shots (M = 2.48, under the loss framework; M = 2.44, under the gain framework); (5) Vaccine protection rate and duration of protection have an impact on people's willingness to vaccinate. Increased willingness to vaccinate when the protection rate of booster vaccine approaches 90% (M = 4.76, under the loss framework; M = 4.68, under the gain framework). When the vaccine protection period is 2 years, people are more willing to receive a booster vaccine; and the willingness to receive a booster shot is stronger under the loss framework (M = 4.60, SD = 0.721, p = 0.879). Conclusion: The impact of the information framework on COVID-19 vaccination intentions is different, and the disclosure of relevant health information should focus on the impact of the information framework and content on the public's behavior toward strengthening vaccination. Therefore, in the face of public health emergencies, public health departments, healthcare institutions, and other sectors can consider adopting the Gainful Information Framework tool to disseminate health information to achieve better persuasion and promote public health behavior change enhancing public health awareness, and promoting universal vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Intenção , COVID-19/prevenção & controle , Vacinação , China
3.
ACS Appl Mater Interfaces ; 16(8): 10093-10103, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38359415

RESUMO

Sulfurized polyacrylonitrile (PAN@S) is a promising cathode material for room-temperature Na/S batteries but suffers from low conductivity and insufficient electrochemical activity, resulting in unsatisfactory actual capacity and rate performance. Herein, Ti3C2Tx MXene nanosheets are used as a conductive and catalytic binder to establish the PAN@S electrode, wherein MXene constructs a highly conductive framework for fast charge transport and provides high catalytic effect to improve the active material utilization and accelerate the redox kinetics significantly. Therefore, the PAN@S electrode bonded by MXene shows an electronic conductivity of 5.05 S cm-1, 4 orders of magnitude higher than the conventional electrodes bonded by the insulative polymer binders, and much decreased activation energy barrier and resistance. Consequently, the PAN@S electrode displays superior performance in terms of high capacity (697.3 mAh g-1 at 200 mA g-1), unparalleled rate capability (189.0 mAh g-1 at 20 A g-1), and excellent high-rate cycling performance (a capacity decay rate of ∼0.04% per cycle during 1000 cycles at 5 A g-1). This work provides a high-performance electrode for room-temperature Na/S batteries and shows the promising potential of conductive and catalytic MXene binders in boosting the performance of active materials.

4.
Small Methods ; 8(3): e2301102, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37926702

RESUMO

To overcome the shuttle effect and improve the energy density of Li-S batteries, developing free-standing sulfur carriers with high capture and catalytic effect towards polysulfides is an effective strategy. Herein, a MXene/reduced graphene oxide/C3 N4 aerogel (MG/C3 N4 ) with three-dimensional architecture prepared through low-temperature hydrothermal approach followed by thermal treatment is used as sulfur carrier for free-standing cathode of Li-S batteries. In the MG/C3 N4 , MXene and rGO construct a highly conductive framework, and the MXene nanosheets offer chemical capture and catalytic activity towards lithium polysulfides, in favor of good cycling stability. The introduction of g-C3 N4 further enhances the reactivity of C-Ti-N at the hetero-interface by engineering the electronic state of Ti atoms, leading to the optimized metal d-band for expediting the multistep conversion of sulfur electrochemistry. Therefore, the free-standing sulfur cathode with MG/C3 N4 carrier achieves excellent performance with a capacity of 1315.6 mAh g-1 at 0.2 C and a capacity retention of 97.5% after 100 cycles as well as superior rate capability with 1167.4 mAh g-1 at 2 C. Even at a high sulfur loading of 4.92 mg cm-2 , the cathode remains 940.3 mAh g-1 (4.62 mAh cm-2 ) after 200 cycles, indicating its promising potential for achieving high-performance Li-S batteries.

5.
ACS Appl Mater Interfaces ; 15(6): 7999-8009, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36719841

RESUMO

Co3O4 is a potential high-capacity anode material for lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs), but the poor electrical conductivity and large volume fluctuations during long-term cycling severely limit its cycle durability and rate capabilities, especially for PIBs with large K-ion size. Here, we propose a sulfur template route to fabricate an integral 3D porous Co3O4/MXene (Ti3C2Tx) foam using simple vacuum co-filtrating an aqueous dispersion of Co3O4, S and MXene followed by calcining to remove the S template. The 3D porous structure can easily accommodate the large volume changes of Co3O4 while maintains electrode structural integrity, allowing to realize outstanding long-term cycle stability when tested as anodes for both LIBs (620.4 mA h g-1 after 1000 cycles at 1 A g-1) and PIBs (134.1 mA h g-1 after 1000 cycles at 0.5 A g-1). The high metallic conductivity of the 3D porous MXene network further facilitates the electron/ion transmission, resulting in an improved rate capability of 390 mA h g-1 at 13 A g-1 for LIBs and 125.3 mA h g-1 at 1 A g-1 for PIBs. The robust performance of the 3D porous Co3O4/MXene foam reflects its perspective as a high-performance anode material for both LIBs and PIBs.

6.
Med Phys ; 50(2): 1205-1214, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36342293

RESUMO

BACKGROUND: Patient-specific quality assurance (PSQA) is an indispensable and essential procedure in radiotherapy workflow, and several studies have been done to develop prediction models based on the conventional C-arm linac of single-layered multileaf collimator (MLC) with machine learning (ML) and deep learning techniques to predict PSQA results and improve efficiency. Recently, a newly designed O-ring gantry linac "Halcyon" equipped with unique jawless stacked-and-staggered dual-layered MLC was released. However, few studies have focused on developing PSQA prediction models for this novel dual-layered MLC system. PURPOSE: To evaluate the performance of ML to predict PSQA results of fixed field intensity-modulated radiation therapy (FF-IMRT) plans for linac equipped with dual-layered MLC. METHODS AND MATERIALS: A total of 213 FF-IMRT treatment plans, including 1383 beams from various treatment sites, were selected and delivered with portal dosimetry verification on Halcyon linac. Gamma analysis was performed using 1%/1, 2%/2, and 3%/2 mm criteria with a 10% threshold. The training set (TS) of ML models consisted of 1106 beams, and an independent evaluation set (ES) consisted of 277 beams. For each beam, 33 complexity metrics were extracted as input data for training models. Three ML algorithms (gradient boosting decision tree/GBDT, random forest/RF, and Poisson Lasso/PL) were utilized to build the models and predict gamma passing rates (GPRs). To improve the prediction accuracy in the rare region, a method of reweighting for TS has been performed and compared to the unweighted results. The importance of complexity metrics was studied by permuted interesting features. RESULTS: The GBDT model had the best performance in this study. In ES, the minimal mean prediction error for unweighted results was 1.93%, 1.16%, 0.78% under 1%/1, 2%/2, and 3%/2 mm criteria, respectively, from GBDT model. Comparing to the unweighted results, the models after reweighting gained up to 30% improvement in the rare region, whereas the overall prediction error was slightly worse depending on the kind of models. For feature importance, 2 tree-based models (GBDT and RF) had in common the top 10 most important metrics as well as the same metric with the largest impact. CONCLUSION: For linac equipped with novel dual-layered MLC, the ML model based on GBDT algorithm shows a certain degree of accuracy for GPRs prediction. The specific ML model for dual-layered MLC configuration could be a useful tool for physicists detecting PSQA measurement failures.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Aprendizado de Máquina , Benchmarking , Radioterapia de Intensidade Modulada/métodos , Radiometria , Dosagem Radioterapêutica
7.
ACS Appl Mater Interfaces ; 14(41): 46502-46512, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36194645

RESUMO

Mn3O4 is regarded as a promising anode material for lithium-ion batteries (LIBs) based on its ultrahigh theoretical capacity (937 mAh g-1) and low cost but suffers from poor electronic conductivity and large volume variation during the lithiation/delithiation process, which result in dramatic capacity fading and inferior rate capability. Ti3C2Tx MXene, a novel two-dimensional transition metal carbide with metallic conductivity, excellent mechanical properties, and hydrophilic surface, could be an ideal candidate to improve the lithium storage performance of Mn3O4. Here, a unique flexible, 2D-2D Mn3O4/MXene film is fabricated by assembling 2D Mn3O4 with Ti3C2Tx nanosheets through a simple vacuum filtration approach. In this unique 2D-2D nanostructure, MXene nanosheets buffer the volume change of Mn3O4 during the charge/discharge process. Moreover, the introduction of MXene enables the fabricated 2D-2D nanostructure with excellent flexibility and can be directly used as an electrode for LIBs, which is beneficial for enhancing the energy density of the assembled batteries. As a result, the flexible film of Mn3O4-MXene-8-2 shows excellent lithium storage performances in terms of specific capacity (931 mAh g-1 at 0.05 A g-1), rate capability (624 mAh g-1 at 1 A g-1), and cycling stability, demonstrating its great potential for the application in LIBs.

8.
World J Clin Cases ; 10(22): 7728-7737, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-36158510

RESUMO

BACKGROUND: Radiation therapy, especially the development of linear accelerators, plays a key role in cancer management. The fast-rotating coplanar O-ring Halcyon Linac has demonstrated many advantages. The previous literature has mainly focused on the machine parameters and plan quality of Halcyon, with a lack of relevant research on its clinical application. AIM: To evaluate the clinical performance of the O-ring Halcyon treatment system in a real-world application setting. METHODS: Data from sixty-one patients who were treated with the Halcyon system throughout the entire radiotherapy process in Peking Union Medical College Hospital between August 2019 and September 2020 were retrospectively reviewed. We evaluated the target tumour response to radiotherapy and irradiation toxicity from 1 to 3 mo after treatment. Dosimetric verification of Halcyon plans was performed using a quality assurance procedure, including portal dosimetry, ArcCHECK and point dose measurements for verification of the system delivery accuracy. RESULTS: Of the 61 patients in the five groups, 16, 12, 7 and 26 patients had complete response, partial response, progressive disease and stable disease, respectively. No increase in the irradiated target tumour volume was observed when separately evaluating the local response. Regarding irradiation toxicity, no radiation-induced deaths were observed. Thirty-eight percent (23/61 patients) had no radiation toxicity after radiotherapy, 56% (34/61 patients) experienced radiation toxicity that resolved after treatment, and 6% (4/61 patients) had irreversible adverse reactions. The average gamma passing rates with a 2% dose difference and 2-mm distance to agreement for IMRT/VMAT/SRT plans were ArcCHECK at 96.4% and portal dosimetry at 96.7%, respectively. All of the validated clinical plans were within 3% for point dose measurements, and Halcyon's ArcCHECK demonstrated a high pass rate of 99.1% ± 1.1% for clinical gamma passing criteria of 3%/3 mm. CONCLUSION: The O-ring Halcyon Linac could achieve a better therapeutic effect on the target volume by providing accurate treatment delivery plans with tolerable irradiation toxicity.

9.
Front Psychol ; 13: 952524, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118472

RESUMO

Background: Family consent is a prerequisite for the organ donation of the deceased in China. However, a large number of donors are individuals who died due to accidental injuries or unanticipated diseases, which means that most of the families of such donors have just experienced the sudden death of their loved one and have to make a donation decision in a short time. This decision may cause psychological stress and some psychological damage to the minds of relatives of the donors. In addition, cultural sensitivity also has largely caused the relatives of donors inner conflicts and contradictions. And sometimes organ donation may still be stigmatized. However, have they received any emotional support and what is their emotional support needs are some questions that need to be answered. Therefore, this study aims to investigate the emotional support, influencing factors, and needs of the family members of organ donors in Hunan Province, China. Materials and methods: This is mixed-methods research that combines quantitative and qualitative research methods. A cross-sectional survey was conducted among 102 donor families using a questionnaire to investigate their emotional support status. To further understand their emotional support needs, 12 donor families participated in the semi-structured interview. Results: The results confirmed that: (1) A total of 67.7% of the 102 respondents received emotional support or psychological comfort. Thus, only a small number of respondents (31.4%) felt respected by the public. (2) Emotional support came mainly from immediate family members (73.91%), and official organizations such as the Red Cross (43.48%). (3) Marital status, health status, occupation, and coping style can affect the emotional support of the donor families (p < 0.05). (4) Interview showed that the families of donors need emotional support and psychological aid from psychological professionals mostly. And they also wish to receive the understanding and respect of the public. Conclusion: Most families of organ donors received emotional support from family, Red Cross, and friends, but only a minority of families of donors reported receiving respect from the public after the donation. And families of donor showed a strong need for emotional support and professional psychological aid from institutions.

10.
Vaccines (Basel) ; 10(8)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36016224

RESUMO

(1) Objective: To explore Chinese residents' willingness to receive COVID-19 vaccine booster shots and identify predictors of the level of willingness based on the health belief model (HBM). (2) Methods: The snowball sampling method was used to distribute online questionnaires. A chi-square test was used to analyze the relationship between different variables. The causal relationship between HBM-related factors and booster vaccination intentions was explored by Structural equation modeling (SEM). (3) Results: A total of 898 complete responses were included; 64.3% had already received the booster injection. Most respondents intended to vaccinate themselves, while 16.1% were hesitant. Nearly half of the respondents chose to take the booster injection to support China's vaccination policy. Using the SEM, perceived susceptibility and perceived barriers were found to have a negative effect on booster vaccination intentions, whereas perceived benefit and cues to action positively affected booster vaccination intentions in the HBM. (4) Conclusions: Factors included in this study have different effects on the willingness to take the COVID-19 booster injections. Sociodemographic characteristics and characteristics of participants' COVID-19 vaccination have a significant effect on the willingness to receive vaccine booster shots. The HBM constructs can serve as good predictors of the acceptance of vaccine booster shots with the exception of perceived severity, which may benefit health officials in terms of conducting targeted strategies in vaccine programs.

11.
Adv Sci (Weinh) ; 9(20): e2200023, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35508900

RESUMO

Sodium-ion batteries (SIBs) are regarded as a kind of promising candidate for large-scale energy storage technology. The development of advanced carbon anodes with high Na-storage capacity and initial Coulombic efficiency (ICE) from low cost, resources abundant precursors is critical for SIBs. Here, a carbon microcrystalline hybridization route to synthesize hard carbons with extensive pseudo-graphitic regions from lignite coal with the assistance of sucrose is proposed. Employing the cross-linked interaction between sucrose and lignite coal to generate carbon-based hybrid microcrystalline states, the obtained hard carbons possess pseudo-graphitic dominant phases with large interlayer spaces that facilitate Na ion's storage and transportation, as well as fewer surface defects that guarantee high ICE. The LCS-73 with an optimum cross-link demonstrates the highest Na-storage capacity of 356 mAh g-1 and an ICE of 82.9%. The corresponding full-cell delivers a high energy density of 240 Wh kg-1 (based on the mass of anode and cathode materials) and excellent rate capability of 106 mAh g-1 at 10 C in addition to outstanding cycle performance with 80% retention over 500 cycles at 2 C. The proposed work offers an efficient route to develop high-performance, low-cost carbon-based anode materials with potential application for advanced SIBs.

12.
Small Methods ; 6(4): e2101537, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35238178

RESUMO

Supercapacitors have the characteristics of high power density and long cycle life, but the low energy density limits their further development. The 2D transitional metal carbides/nitrides (MXenes) show great application prospects in the field of supercapacitors due to their superior volumetric capacitance, metallic-like conductivity, tunable surface terminations, and structural advantages. However, like other 2D materials, MXenes suffer from the inevitable problem of nanosheet restacking and aggregation, which reduces the overall active surface sites and blocks the accessibility of the electrolyte ions. The transformation of 2D MXene nanosheets into 3D architectures is proven effective to overcome the restacking problem. The review briefly summarizes the preparation strategies of 3D MXene materials, including template-assisted method, framework-assisted method, chemical assembly method, foaming method, and other methods with the discussion centered on the performances of 3D MXenes in supercapacitors. Finally, an outlook on the current progress and opportunities is given to highlight the increasing popularity of 3D MXenes in supercapacitors.

13.
Cancer Med ; 11(1): 28-39, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34783168

RESUMO

PURPOSE: To validate the nodal center coverage (NCC) of the three mainstream delineation methods of para-aortic nodal clinical target volume (CTV) and propose a modified delineation method of para-aortic nodal CTV in prophylactic extended-field irradiation (EFI) of cervical cancer. METHODS: A total of 106 patients with para-aortic lymph nodes (PALNs) identified on PET/CT were included at Peking Union Medical College Hospital between 2011 and 2020. PALNs were classified as left lateral para-aortic (LLPA), aorto-caval (AC), and right para-caval (RPC). Distances from the nodal center to the aorta and inferior vena cava (IVC) were measured. The NCC of the three mainstream delineation methods of para-aortic nodal CTV (CTV-K, CTV-S, and CTV-D) and a modified CTV (CTV-M) was calculated. Radiotherapy plans were created based on 4 CTVs for 10 selected patients who received prophylactic EFI. The chi-squared test and the Student's t-test were performed. RESULTS: We identified 344 PALNs (216 LLPA, 101 AC, and 27 RPC) in 106 patients. Mean distance from the nodal center to the aorta was 9.6 mm in the LLPA and 7 mm in the AC and from the nodal center to the IVC was 5.6 mm in the AC and 5.6 mm in the RPC. CTV-D improved the NCC of 98% compared with 92% for CTV-K (p = 0.002) and 95% for CTV-S (p = 0.046). CTV-M provided the same satisfactory NCC as CTV-D (97% vs. 98%, p = 0.485). The V50Gy to the duodenum, the Dmean to the bilateral kidneys, and the V45Gy to the small bowel were significantly lower on the CTV-M-based plan than on the CTV-D-based plan (p = 0.001, 0.011, and 0.001, respectively). CONCLUSION: CTV-D provided more satisfactory NCC than CTV-K and CTV-S. CTV-M provided the same satisfactory NCC as CTV-D and reduced the dose to the critical structures.


Assuntos
Linfonodos/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiometria , Dosagem Radioterapêutica , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia
14.
Nanomicro Lett ; 13(1): 202, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34568995

RESUMO

ZnS has great potentials as an anode for lithium storage because of its high theoretical capacity and resource abundance; however, the large volume expansion accompanied with structural collapse and low conductivity of ZnS cause severe capacity fading and inferior rate capability during lithium storage. Herein, 0D-2D ZnS nanodots/Ti3C2Tx MXene hybrids are prepared by anchoring ZnS nanodots on Ti3C2Tx MXene nanosheets through coordination modulation between MXene and MOF precursor (ZIF-8) followed with sulfidation. The MXene substrate coupled with the ZnS nanodots can synergistically accommodate volume variation of ZnS over charge-discharge to realize stable cyclability. As revealed by XPS characterizations and DFT calculations, the strong interfacial interaction between ZnS nanodots and MXene nanosheets can boost fast electron/lithium-ion transfer to achieve excellent electrochemical activity and kinetics for lithium storage. Thereby, the as-prepared ZnS nanodots/MXene hybrid exhibits a high capacity of 726.8 mAh g-1 at 30 mA g-1, superior cyclic stability (462.8 mAh g-1 after 1000 cycles at 0.5 A g-1), and excellent rate performance. The present results provide new insights into the understanding of the lithium storage mechanism of ZnS and the revealing of the effects of interfacial interaction on lithium storage performance enhancement.

15.
Adv Mater ; 33(39): e2103148, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34423479

RESUMO

2D transition metal carbides, nitrides, and carbonitrides, also known as MXenes, are versatile materials due to their adjustable structure and rich surface chemistry. The physical and chemical diversity has recognized MXenes as a potential 2D material with a wide spectrum of application domains. Since the discovery of MXenes in 2011, a wide variety of synthetic routes has been proposed with advancement toward large-scale preparing methods for MXene nanosheets and derivative products. Herein, the critical synthesis aspects and the operating conditions that influence the physical and chemical characteristics of MXenes are discussed in detail. The emerging etching methods including HF etching methods, in situ HF-forming etching methods, electrochemical etching methods, alkali etching methods, and molten salt etching methods, as well as delamination strategies are discussed. Considering the future developments and practical applications, the large-scale synthesis routes and the antioxidation strategies of MXenes are also summarized. In summary, a generalized overview of MXenes synthesis protocols with an outlook for the current challenges and promising technologies for large-scale preparation and stable storage is provided.

16.
ChemSusChem ; 14(12): 2501-2515, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33830655

RESUMO

"Water-in-salt" (WIS) electrolytes, which have more salt than the solvent in both mass and volume, show promising prospects for application in supercapacitors due to their wide electrochemical stability window (about 3 V), considerable ion transport, high safety, low cost, and environmental friendliness. This Review summarizes the advances, progress, and challenges of WIS electrolytes in supercapacitors. The working mechanisms, reason for the wide electrochemical stability window, typical systems, challenges, and modification strategies of the WIS electrolytes in supercapacitors are discussed. Moreover, the application of WIS electrolytes in symmetric and asymmetric supercapacitors are presented. Finally, perspectives and the future development direction of WIS electrolytes are given. This Review is expected to provide inspiration and guidance for designing WIS electrolytes with advanced performance and push forward the development of high-performance aqueous supercapacitors with high cell voltage, good rate performance, and thus high energy density and power density.

17.
Nano Converg ; 8(1): 5, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33594612

RESUMO

MXenes have recently been recognized as potential materials based on their unique physical and chemical characteristics. The widely growing family of MXenes is rapidly expanding their application domains since their first usage as energy materials was reported in 2011. The inherent chemical nature, high hydrophilicity, and robust electrochemistry regard MXenes as a promising avenue for environment-remediation technologies such as adsorption, membrane separation, photocatalysis and the electrocatalytic sensor designed for pollutant detection. As the performance of MXenes in these technologies is on a continuous path to improvement, this review intends to cumulatively discuss the diversity and chemical abilities of MXenes and their hybrid composites in the fields mentioned above with a focus on MXenes improving surface-characteristics. The review is expected to promote the diversity of MXenes and their hybrid configuration for advanced technologies widely applied for environmental remediation.

19.
Nanomicro Lett ; 12(1): 89, 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-34138104

RESUMO

MXene nanosheets have been used for preparing highly flexible integrated electrodes due to their two-dimensional (2D) morphology, flexibility, high conductivity, and abundant functional groups. However, restacking of 2D nanosheets inhibits the ion transport in MXene electrodes, limiting their thickness, rate performance, and energy storage capacity. Here, we employed a natural sedimentation method instead of the conventional vacuum-assisted filtration to prepare flexible Ti3C2Tx MXene films with enlarged interlayer spacing, which facilitates the access of the lithium ions to the interlayers and thus leads to a greatly enhanced electrochemical performance. The naturally sedimented flexible film shows a double lithium storage capacity compared to the conventional vacuum-filtered MXene film, along with improved rate performance and excellent cycle stability.

20.
ChemSusChem ; 13(6): 1621-1628, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31318177

RESUMO

Silicon is a promising anode material with high capacity for lithium-ion batteries (LIBs) but suffers from poor conductivity and large volume change during charge/discharge. Herein, by using two-dimensional conductive MXene as a multifunctional binder instead of conventional insulating polymer binders such as poly(vinylidene fluoride) or carboxymethylcellulose sodium (PVDF and CMC, respectively), a free-standing, flexible Si@C film was fabricated by simple vacuum filtration and directly used as anode for LIBs. In the MXene-bonded Si@C film, MXene constructed a three-dimensional conductive framework in which Si@C nanocomposites were embedded. Its loose and porous structure provided much space to buffer the large volume expansion of Si@C nanoparticles and thus led to significantly superior cycle stability compared with conventional CMC- and PVDF-bonded Si@C electrodes. Moreover, the porous structure and the metallically conductive MXene offered fast ion transport and outstanding conductivity of the MXene-bonded Si@C film, which were favorable for its rate performance. These results promise good potential of the MXene-bonded Si@C film electrode for LIBs.

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