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1.
Proc Natl Acad Sci U S A ; 120(41): e2310714120, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782794

RESUMO

The future application of Li metal batteries (LMBs) at scale demands electrolytes that endow improved performance under fast-charging and low-temperature operating conditions. Recent works indicate that desolvation kinetics of Li+ plays a crucial role in enabling such behavior. However, the modulation of this process has typically been achieved through inducing qualitative degrees of ion pairing into the system. In this work, we find that a more quantitative control of the ion pairing is crucial to minimizing the desolvation penalty at the electrified interface and thus the reversibility of the Li metal anode under kinetic strain. This effect is demonstrated in localized electrolytes based on strongly and weakly bound ether solvents that allow for the deconvolution of solvation chemistry and structure. Unexpectedly, we find that maximum degrees of ion pairing are suboptimal for ultralow temperature and high-rate operation and that reversibility is substantially improved via slight local dilution away from the saturation point. Further, we find that at the optimum degree of ion pairing for each system, weakly bound solvents still produce superior behavior. The impact of these structure and chemistry effects on charge transfer are then explicitly resolved via experimental and computational analyses. Lastly, we demonstrate that the locally optimized diethyl ether-based localized-high-concentration electrolytes supports kinetic strained operating conditions, including cycling down to -60 °C and 20-min fast charging in LMB full cells. This work demonstrates that explicit, quantitative optimization of the Li+ solvation state is necessary for developing LMB electrolytes capable of low-temperature and high-rate operation.

2.
Proc Natl Acad Sci U S A ; 119(28): e2200392119, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35787034

RESUMO

All-climate temperature operation capability and increased energy density have been recognized as two crucial targets, but they are rarely achieved together in rechargeable lithium (Li) batteries. Herein, we demonstrate an electrolyte system by using monodentate dibutyl ether with both low melting and high boiling points as the sole solvent. Its weak solvation endows an aggregate solvation structure and low solubility toward polysulfide species in a relatively low electrolyte concentration (2 mol L-1). These features were found to be vital in avoiding dendrite growth and enabling Li metal Coulombic efficiencies of 99.0%, 98.2%, and 98.7% at 23 °C, -40 °C, and 50 °C, respectively. Pouch cells employing thin Li metal (50 µm) and high-loading sulfurized polyacrylonitrile (3.3 mAh cm-2) cathodes (negative-to-positive capacity ratio = 2) output 87.5% and 115.9% of their room temperature capacity at -40 °C and 50 °C, respectively. This work provides solvent-based design criteria for a wide temperature range Li-sulfur pouch cells.

3.
Angew Chem Int Ed Engl ; 63(5): e202316786, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38058265

RESUMO

Achieving increased energy density under extreme operating conditions remains a major challenge in rechargeable batteries. Herein, we demonstrate an all-fluorinated ester-based electrolyte comprising partially fluorinated carboxylate and carbonate esters. This electrolyte exhibits temperature-resilient physicochemical properties and moderate ion-paired solvation, leading to a half solvent-separated and half contact-ion pair in a sole electrolyte. As a result, facile desolvation and preferential reduction of anions/fluorinated co-solvents for LiF-dominated interphases are achieved without compromising ionic conductivity (>1 mS cm-1 even at -40 °C). These advantageous features were found to apply to both lithium metal and sulfur-based electrodes even under extreme operating conditions, allowing stable cycling of Li || sulfurized polyacrylonitrile (SPAN) full cells with high SPAN loading (>3.5 mAh cm-2 ) and thin Li anode (50 µm) at -40, 23 and 50 °C. This work offers a promising path for designing temperature-resilient electrolytes to support high energy density Li metal batteries operating in extreme conditions.

4.
Int J Mol Sci ; 21(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150966

RESUMO

Mulberry sclerotiniose caused by Ciboria shiraiana is a devastating disease of mulberry (Morus alba L.) fruit in Northwest China. At present, no disease-resistant varieties are used in production, as the molecular mechanisms of this disease are not well understood. In this study, to explore new prevention methods and provide direction for molecular breeding, transcriptomic sequencing and un-targeted metabolomics were performed on healthy (CK), early-stage diseased (HB1), and middle-stage diseased (HB2) mulberry fruits. Functional annotation, gene ontology, a Kyoto encyclopedia of genes and genomes (KEGG) analysis, and a Mapman analysis of the differentially expressed genes revealed differential regulation of genes related to plant hormone signal transduction, transcription factors, and phenylpropanoid biosynthesis. A correspondence between the transcript pattern and metabolite profile was observed in the phenylpropanoid biosynthesis pathway. It should be noted that the log2 ratio of eugenol (isoeugenol) in HB1 and HB2 are 85 times and 23 times higher than CK, respectively. Our study shows that phenylpropanoid biosynthesis may play an essential role in response to sclerotiniose pathogen infection and eugenol(isoeugenol) enrichment in mulberry fruit, which may provide a novel method for mulberry sclerotiniose control.


Assuntos
Ascomicetos/fisiologia , Frutas/imunologia , Metaboloma , Morus/imunologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Transcriptoma , Frutas/genética , Frutas/metabolismo , Frutas/microbiologia , Regulação da Expressão Gênica de Plantas , Morus/genética , Morus/metabolismo , Morus/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética
5.
ACS Nano ; 18(24): 15671-15680, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38837180

RESUMO

While nanostructural engineering holds promise for improving the stability of high-capacity silicon (Si) anodes in lithium-ion batteries (LIBs), challenges like complex synthesis and the high cost of nano-Si impede its commercial application. In this study, we present a local reduction technique to synthesize micron-scale monolithic layered Si (10-20 µm) with a high tap density of 0.9-1.0 g cm-3 from cost-effective montmorillonite, a natural layered silicate mineral. The created mesoporous structure within each layer, combined with the void spaces between interlayers, effectively mitigates both lateral and vertical expansion throughout repeated lithiation/delithiation cycles. Furthermore, the remaining SiO2 network fortifies the layered structure, preventing it from collapsing during cycling. Half-cell tests reveal a capacity retention of 92% with a reversible capacity of 1130 mAh g-1 over 500 cycles. Moreover, the pouch cell integrated with this Si anode (with a mass loading of 3.0 mg cm-2) and a commercial NCM811 cathode delivers a high energy density of 655 Wh kg-1 (based on the total mass of the cathode and anode) and maintains 82% capacity after 200 cycles. This work demonstrates a cost-efficient and scalable strategy to manufacture high-performance micron Si anodes for the ever-growing demand for high-energy LIBs.

6.
Glob Chall ; 6(12): 2200099, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36532242

RESUMO

Li-ion battery (LIB) recycling has become an urgent need with rapid prospering of the electric vehicle (EV) industry, which has caused a shortage of material resources and led to an increasing amount of retired batteries. However, the global LIB recycling effort is hampered by various factors such as insufficient logistics, regulation, and technology readiness. Here, the challenges associated with LIB recycling and their possible solutions are summarized. Different aspects such as recycling/upcycling techniques, worldwide government policies, and the economic and environmental impacts are discussed, along with some practical suggestions to overcome these challenges for a promising circular economy for LIB materials. Some potential strategies are proposed to convert such challenges into opportunities to maintain the global expansion of the EV and other LIB-dependent industries.

7.
Nanoscale ; 13(5): 2811-2819, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33508048

RESUMO

Nickel (Ni)-rich layered oxides such as LiNi0.6Co0.2Mn0.2O2 (NCM622) represent one of the most promising candidates for next-generation high-energy lithium-ion batteries (LIBs). However, the pristine Ni-rich cathode materials usually suffer from poor structural stability during cycling. In this work, we demonstrate a simple but effective approach to improve the cycling stability of the NCM622 cathode by dry coating of ultrastable Li3V2(PO4)3-carbon (LVP-C) nanoparticles, which leads to a robust composite cathode (NCM622/LVP-C) without sacrificing the specific energy density compared with pristine NCM622. The optimal NCM622/LVP-C composite presents a high specific capacity of 162 mA h g-1 at 0.5 C and excellent cycling performance with 85.0% capacity retention after 200 cycles at 2 C, higher than that of the pristine NCM622 (67.6%). Systematic characterization confirms that the LVP-C protective layer can effectively reduce the side reactions, restrict the cation mixing of NCM622 and improve its structural stability. Moreover, the NCM622/LVP-C||graphite full cells also show a commercial-level capacity of 3.2 mA h cm-2 and much improved cycling stability compared with NCM622/LVP-C||graphite full cells, indicating the great promise for low-cost, high-capacity and long-life LIBs.

8.
Chemosphere ; 245: 125587, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864062

RESUMO

Natural biomass is a renewable source for precursors of porous carbon. Four agriculture wastes of corn cob (CC), wheat bran (WB), rice husk (RH), and soybean shell (SS) were applied to produce activated carbons (ACs) via one-step activation by sodium hydroxide. The effects of ash contents and NaOH dosage ratio (1-5) on surface area for ACs were investigated. Owing to ash etching, the high ash precursor (like RH) exhibited less alkali consumption and larger surface area than low ash one (like CC). All four ACs expressed developed pore structure and outstanding surface area of ∼2500 m2g-1. During adsorption of lead ions in simulated wastewater, RH-based AC revealed superior capture capacity of 492 ± 15 mgg-1. One-step activation had the potential to deliver savings around 1/3 of energy consumption, enabling the cost performance of high ash RH-based AC reaching 194 ± 12 g Pb2+$-1, 76% larger than low ash CC-based AC. High ash biomass is a promising candidate to obtain eco-friendly carbon products.


Assuntos
Agricultura , Chumbo/química , Modelos Químicos , Adsorção , Álcalis , Biomassa , Carvão Vegetal/química , Oryza , Porosidade , Eliminação de Resíduos , Hidróxido de Sódio , Resíduos
9.
ACS Appl Mater Interfaces ; 12(46): 51546-51554, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33151665

RESUMO

Due to the large demand of lithium-ion batteries (LIBs) for energy storage in daily life and the limited lifetime of commercial LIB cells, exploring green and sustainable recycling methods becomes an urgent need to mitigate the environmental and economic issues associated with waste LIBs. In this work, we demonstrate an efficient direct recycling method to regenerate degraded lithium manganese oxide (LMO) cathodes to restore their high capacity, long cycling stability, and high rate performance, on par with pristine LMO materials. This one-step regeneration, achieved by a hydrothermal reaction in dilution Li-containing solution, enables the reconstruction of desired stoichiometry and microphase purity, which is further validated by testing spent LIBs with different states of health. Life-cycle analysis suggested the great environmental and economic benefits enabled by this direct regeneration method compared with today's pyro- and hydrometallurgical processes. This work not only represents a fundamental understanding of the relithiation mechanism of spent cathodes but also provides a potential solution for sustainable and closed-loop recycling and remanufacturing of energy materials.

10.
Nat Commun ; 11(1): 2178, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358548

RESUMO

Electrochemical synthesis of H2O2 through a selective two-electron (2e-) oxygen reduction reaction (ORR) is an attractive alternative to the industrial anthraquinone oxidation method, as it allows decentralized H2O2 production. Herein, we report that the synergistic interaction between partially oxidized palladium (Pdδ+) and oxygen-functionalized carbon can promote 2e- ORR in acidic electrolytes. An electrocatalyst synthesized by solution deposition of amorphous Pdδ+ clusters (Pd3δ+ and Pd4δ+) onto mildly oxidized carbon nanotubes (Pdδ+-OCNT) shows nearly 100% selectivity toward H2O2 and a positive shift of ORR onset potential by ~320 mV compared with the OCNT substrate. A high mass activity (1.946 A mg-1 at 0.45 V) of Pdδ+-OCNT is achieved. Extended X-ray absorption fine structure characterization and density functional theory calculations suggest that the interaction between Pd clusters and the nearby oxygen-containing functional groups is key for the high selectivity and activity for 2e- ORR.

11.
Nano Res ; 12: 273-279, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31832124

RESUMO

Theranostic nanoparticles are integrated systems useful for simultaneous diagnosis and imaging guided delivery of therapeutic drugs, with wide ranging potential applications in the clinic. Here we developed a theranostic nanoparticle (~ 24 nm size by dynamic light scattering) p-FE-PTX-FA based on polymeric micelle encapsulating an organic dye (FE) fluorescing in the 1,000-1,700 nm second near-infrared (NIR-II) window and an anti-cancer drug paclitaxel. Folic acid (FA) was conjugated to the nanoparticles to afford specific binding to molecular folate receptors on murine breast cancer 4T1 tumor cells. In vivo, the nanoparticles accumulated in 4T1 tumor through both passive and active targeting effect. Under an 808 nm laser excitation, fluorescence detection above 1,300 nm afforded a large Stokes shift, allowing targeted molecular imaging tumor with high signal to background ratios, reaching a high tumor to normal tissue signal ratio (T/NT) of (20.0 ± 2.3). Further, 4T1 tumors on mice were completed eradicated by paclitaxel released from p-FE-PTA-FA within 20 days of the first injection. Pharmacokinetics and histology studies indicated p-FE-PTX-FA had no obvious toxic side effects to major organs. This represented the first NIR-II theranostic agent developed.

12.
Nat Commun ; 9(1): 1171, 2018 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-29563581

RESUMO

Fluorescence imaging of biological systems in the second near-infrared (NIR-II, 1000-1700 nm) window has shown promise of high spatial resolution, low background, and deep tissue penetration owing to low autofluorescence and suppressed scattering of long wavelength photons. Here we develop a bright organic nanofluorophore (named p-FE) for high-performance biological imaging in the NIR-II window. The bright NIR-II >1100 nm fluorescence emission from p-FE affords non-invasive in vivo tracking of blood flow in mouse brain vessels. Excitingly, p-FE enables one-photon based, three-dimensional (3D) confocal imaging of vasculatures in fixed mouse brain tissue with a layer-by-layer imaging depth up to ~1.3 mm and sub-10 µm high spatial resolution. We also perform in vivo two-color fluorescence imaging in the NIR-II window by utilizing p-FE as a vasculature imaging agent emitting between 1100 and 1300 nm and single-walled carbon nanotubes (CNTs) emitting above 1500 nm to highlight tumors in mice.


Assuntos
Encéfalo/diagnóstico por imagem , Corantes Fluorescentes/farmacocinética , Imageamento Tridimensional/métodos , Nanotubos de Carbono/química , Imagem Óptica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/fisiologia , Encéfalo/irrigação sanguínea , Linhagem Celular Tumoral , Circulação Cerebrovascular/fisiologia , Feminino , Corantes Fluorescentes/síntese química , Imageamento Tridimensional/instrumentação , Injeções Subcutâneas , Glândulas Mamárias Animais/irrigação sanguínea , Glândulas Mamárias Animais/diagnóstico por imagem , Glândulas Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Imagem Óptica/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação
13.
Adv Mater ; 30(22): e1800106, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29682821

RESUMO

In vivo molecular imaging of tumors targeting a specific cancer cell marker is a promising strategy for cancer diagnosis and imaging guided surgery and therapy. While targeted imaging often relies on antibody-modified probes, peptides can afford targeting probes with small sizes, high penetrating ability, and rapid excretion. Recently, in vivo fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) shows promise in reaching sub-centimeter depth with microscale resolution. Here, a novel peptide (named CP) conjugated NIR-II fluorescent probe is reported for molecular tumor imaging targeting a tumor stem cell biomarker CD133. The click chemistry derived peptide-dye (CP-IRT dye) probe afforded efficient in vivo tumor targeting in mice with a high tumor-to-normal tissue signal ratio (T/NT > 8). Importantly, the CP-IRT probes are rapidly renal excreted (≈87% excretion within 6 h), in stark contrast to accumulation in the liver for typical antibody-dye probes. Further, with NIR-II emitting CP-IRT probes, urethra of mice can be imaged fluorescently for the first time noninvasively through intact tissue. The NIR-II fluorescent, CD133 targeting imaging probes are potentially useful for human use in the clinic for cancer diagnosis and therapy.


Assuntos
Peptídeos/química , Animais , Linhagem Celular Tumoral , Química Click , Corantes Fluorescentes , Camundongos , Imagem Molecular , Espectroscopia de Luz Próxima ao Infravermelho
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(5): 1037-41, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17956686

RESUMO

The objective of this study was to investigate the change of native immune adhering function (ENIAF) in self-plasma of patients with hematologic and lymphoid neoplasms and its effect on the killing activity of NK cells. The whole blood was anticoagulated with citric acid. 5 microl precipitated red blood cells and 500 microl plasma of patients or controls were directly mixed with 750 microl quantitative K562 cells at 37 degrees C for 30 minutes. One K562 cell attached by one or more erythrocytes was counted as one rosette, the ratio of rosettes was calculated. Using K562 cells as target cells, the killing activity of NK cells isolated from normal persons was detected by MTT assay, the change of the killing activity was observed after adding RBCs. The results indicated that the ratio of rosettes formed by RBCs of 21 normal controls and K562 cells was 15.3% +/- 6.4%, and the ratio of rosettes formed by RBCs of 24 patients and K562 cells was 7.6% +/- 7.0%. The ability of ENIAF in patients with hematologic and lymphoid neoplasms was significantly lower than that in healthy individuals (t = 3.61, p < 0.001). The killing rate of NK cells in peripheral blood of normal individuals was 67% - 71% without adding RBCs, and it increased by 14.7% +/- 5.2% after adding RBCs of normal controls but decreased by 4.3% +/- 7.6% with RBCs of patients. It is concluded that the ENIAF of RBCs in patients with hematopoietic and lymphoid neoplasms decreases, accompanying the reduction of the killing activity of NK cells to K562 cells, so to detect change of ENIAF may be helpful for the assessment of the immunological function of patients with hematopoietic and lymphoid neoplasms.


Assuntos
Eritrócitos/imunologia , Neoplasias Hematológicas/imunologia , Reação de Imunoaderência , Células Matadoras Naturais/imunologia , Linfoma/imunologia , Adolescente , Adulto , Humanos , Células K562 , Pessoa de Meia-Idade , Formação de Roseta , Adulto Jovem
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