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1.
Small ; : e2400272, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623970

RESUMO

Polymer-in-salt solid-state electrolytes (PIS SSEs) are emerging for high room-temperature ionic conductivity and facile handling, but suffer from poor mechanical durability and large thickness. Here, Al2O3-coated PE (PE/AO) separators are proposed as robust and large-scale substrates to trim the thickness of PIS SSEs without compromising mechanical durability. Various characterizations unravel that introducing Al2O3 coating on PE separators efficiently improves the wettability, thermal stability, and Li-dendrite resistance of PIS SSEs. The resulting PE/AO@PIS demonstrates ultra-small thickness (25 µm), exceptional mechanical durability (55.1 MPa), high decomposition temperature (330 °C), and favorable ionic conductivity (0.12 mS cm-1 at 25 °C). Consequently, the symmetrical Li cells remain stable at 0.1 mA cm-2 for 3000 h, without Li dendrite formation. Besides, the LiFePO4|Li full cells showcase excellent rate capability (131.0 mAh g-1 at 10C) and cyclability (93.6% capacity retention at 2C after 400 cycles), and high-mass-loading performance (7.5 mg cm-2). Moreover, the PE/AO@PIS can also pair with nickel-rich layered oxides (NCM811 and NCM9055), showing a remarkable specific capacity of 165.3 and 175.4 mAh g-1 at 0.2C after 100 cycles, respectively. This work presents an effective large-scale preparation approach for mechanically durable and ultrathin PIS SSEs, driving their practical applications for next-generation solid-state Li-metal batteries.

2.
Angew Chem Int Ed Engl ; 63(15): e202400621, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38334221

RESUMO

Photo-assisted ion batteries utilize light to boost capacity but face cycling instability due to complex charge/ion transfer under illumination. This study identified photo-induced proton transfer (photo-induced PT) as a significant process in photo-(dis)charging of widely-used V2O5-based zinc-ion batteries, contributing to enhanced capacity under illumination but jeopardizing photo-stability. Photo-induced PT occurs at 100 ps after photo-excitation, inducing rapid proton extraction into V2O5 photoelectrode. This process creates a proton-deficient microenvironment on surface, leading to repetitive cathode dissolution and anode corrosion in each cycle. Enabling the intercalated protons from photo-induced PT to be reversibly employed in charge-discharge processes via the anode-alloying strategy achieves high photo-stability for the battery. Consequently, a ~54 % capacity enhancement was achieved in a V2O5-based zinc-ion battery under illumination, with ~90 % capacity retention after 4000 cycles. This extends the photo-stability record by 10 times. This study offers promising advancements in energy storage by addressing instability issues in photo-assisted ion batteries.

3.
Nanotechnology ; 34(32)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37146591

RESUMO

Since current graphite-based lithium-ion battery anode has a low theoretical capacity, the development of high-performance lithium-ion battery is severely restricted. Here, novel hierarchical composites composing of microdisc and the secondarily grown nanosheets and nanowires are developed, taking NiMoO4nanosheets and Mn3O4nanowires growing on Fe2O3microdiscs as demonstrating examples. The growth processes of the hierarchical structures have been investigated by adjusting a series of preparation conditions. The morphologies and structures have been characterized by using scanning electron microscopy, transmission electron microscope and x-ray diffraction. Fe2O3@Mn3O4composite-based anode displays a capacity of 713 mAh g-1after 100 cycles at 0.5 A g-1with a high Coulombic efficiency. A good rate-performance is also achieved. Fe2O3@NiMoO4anode delivers 539 mAh g-1after 100 cycles at 0.5 A g-1, which is obviously higher than that of pure Fe2O3. The hierarchical structure is conducive to improve the transport of electrons and ions, and provide numerous active sites, thus significantly enhancing the electrochemical performance. Moreover, the electron transfer performance is investigated by using density functional theory calculations. It is expected the findings presented here and the rational engineering of nanosheets/nanowires on microdiscs would be applicable for developing many other high-performance energy-storage composites.

4.
Int Orthop ; 47(3): 781-791, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36348088

RESUMO

PURPOSE: Kashin-Beck disease (KBD) is an endemic osteoarthropathy affecting the epiphyseal growth plate of multiple joints in young and adolescent patients. Previous studies have focused on the visible deformed extremities instead of the spinal radiological features, especially the atlantoaxial joint. The aim of this study was to determine the prevalence and radiographic features of atlantoaxial dislocation (AAD) in adult patients with KBD. METHODS: This study was conducted on KBD patients in three typical endemic counties between October 2017 and November 2019. The patients were evaluated by collecting basic information, clinical signs and symptoms. They underwent dynamic cervical radiography, by which AAD was diagnosed. For those patients with confirmed or suspected AAD, computed tomography (CT) imaging was performed to observe the odontoid morphology and degenerative changes in the lateral atlantoaxial joints. Radiographic evaluations were reviewed to determine the prevalence and features of AAD. RESULTS: A total of 39 (14.6%) of 267 KBD patients were diagnosed with AAD. Compared with the non-AAD patients, the detection rate of AAD was associated with a longer disease duration and stage and was not associated with age, sex or BMI. Thirty-two patients had symptoms at the neck or neurological manifestations, while seven had no symptoms. There were three types of morphologies of the odontoid process in AAD patients: separating in 19 cases, hypoplastic in 15 cases and intact in five cases. Anterior dislocation was noted in 29 cases, and posterior dislocation was noted in ten cases. Thirty-four cases were reducible, and five were irreducible. The lateral atlantoaxial joints had different severities of degenerative changes in 17 cases. CONCLUSIONS: This study revealed that the prevalence of AAD was 14.6% in adult KBD patients. The radiographic features of AAD include manifestations of odontoid dysplasia and chronic degenerative changes in atlantoaxial joints. KBD patients with severe stages and longer disease duration were more vulnerable to the occurrence of AAD. We postulate that this atlantoaxial anomaly might originate from chondronecrosis of the epiphyseal growth plate of the odontoid process in young and adolescent individuals. This study may provide a clinical reference to help clinicians screen, prevent and treat AAD in adult patients with KBD.


Assuntos
Articulação Atlantoaxial , Luxações Articulares , Doença de Kashin-Bek , Adolescente , Humanos , Adulto , Doença de Kashin-Bek/complicações , Prevalência , Radiografia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/epidemiologia , Luxações Articulares/complicações , Tomografia Computadorizada por Raios X , Articulação Atlantoaxial/diagnóstico por imagem
5.
Chem Soc Rev ; 49(2): 433-464, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31939475

RESUMO

Hydrogels are a unique class of polymeric materials that possess an interconnected porous network across various length scales from nano- to macroscopic dimensions and exhibit remarkable structure-derived properties, including high surface area, an accommodating matrix, inherent flexibility, controllable mechanical strength, and excellent biocompatibility. Strong and robust adhesion between hydrogels and substrates is highly desirable for their integration into and subsequent performance in biomedical devices and systems. However, the adhesive behavior of hydrogels is severely weakened by the large amount of water that interacts with the adhesive groups reducing the interfacial interactions. The challenges of developing tough hydrogel-solid interfaces and robust bonding in wet conditions are analogous to the adhesion problems solved by marine organisms. Inspired by mussel adhesion, a variety of catechol-functionalized adhesive hydrogels have been developed, opening a door for the design of multi-functional platforms. This review is structured to give a comprehensive overview of adhesive hydrogels starting with the fundamental challenges of underwater adhesion, followed by synthetic approaches and fabrication techniques, as well as characterization methods, and finally their practical applications in tissue repair and regeneration, antifouling and antimicrobial applications, drug delivery, and cell encapsulation and delivery. Insights on these topics will provide rational guidelines for using nature's blueprints to develop hydrogel materials with advanced functionalities and uncompromised adhesive properties.


Assuntos
Biomimética , Catecóis/química , Hidrogéis/química , Adesivos/química , Propriedades de Superfície
6.
Small ; 16(35): e2000698, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32776405

RESUMO

The realizing of high-performance rechargeable aqueous zinc-ion batteries (ZIBs) with high energy density and long cycling life is promising but still challenging due to the lack of suitable layered cathode materials. The work reports the excellent zinc-ion storage performance as-observed in few-layered ultrathin VSe2 nanosheets with a two-step Zn2+ intercalation/de-intercalation mechanism verified by ex situ X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations. The VSe2 nanosheets exhibit a discharge plateau at 1.0-0.7 V, a specific capacity of 131.8 mAh g-1 (at 0.1 A g-1 ), and a high energy density of 107.3 Wh kg-1 (at a power density of 81.2 W kg-1 ). More importantly, outstanding cycle stability (capacity retention of 80.8% after 500 cycles) without any activation process is achieved. Such a prominent cyclic stability should be attributed to its fast Zn2+ diffusion kinetics (DZn 2+  ≈ 10-8 cm-2 s-1 ) and robust structural/crystalline stability. Density functional theory (DFT) calculation further reveals a strong metallic characteristic and optimal zinc-ion diffusion pathway with a hopping energy barrier of 0.91 eV. The present finding implies that 2D ultrathin VSe2 is a very promising cathode material in ZIBs with remarkable battery performance superior to other layered transitional metal dichalcogenides.

7.
Mol Cell Biochem ; 459(1-2): 205-214, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31227976

RESUMO

Osteoarthritis (OA) is characterized by degradation of articular cartilage. MiRNAs are involved in the regulation of chondrogenesis and OA. We aimed to investigate effects and mechanisms of miR-19b-3p in regulating chondrocytes viability, cartilage degradation and inflammatory response. Primary chondrocytes were isolated from cartilages in control subjects and patients with OA. Murine ATDC5 cells were pre-conditioned with IL-1ß in vitro. Expressions and interaction of miR-19b-3p with G protein-coupled receptor kinase 6 (GRK6), and their effects on inflammation, chondrocytes viability and cartilage degradation were determined after miR-19b-3p mimic or GRK6 siRNA transfection. MiR-19b-3p was significantly decreased in OA chondrocytes and IL-1ß-stimulated ATDC5 cells, in paralleled with the elevated type-II-collagen, aggrecan, MMP13 and GRK6 expression. MiR-19b-3p mimic dramatically increased the viability of chondrocytes and suppressed cell apoptosis. It also increased type-II-collagen, aggrecan expression and glycosaminoglycan (sGAG) content, and decreased the expression of MMP-1 and MMP-13 that controlled by IL-1ß. Overexpression of miR-19b-3p inhibited the production of IL-6 and IL-8 in ATDC5 cells. However, the protective effects of miR-19b-3p mimic on IL-1ß induced cell death; IL-8 production and sGAG decrease were greatly discounted by GRK6 lentiviral vectors. Luciferase reporter assay confirmed that GRK6 gene was a direct target ofmiR-19b-3p. GRK6 siRNA transfection antagonized the IL-1ß-induced chondrocytes injury, extracellular matrix degradation and inflammatory response. MiR-19b-3p mimic and GRK6 siRNA showed comparable inhibitory effect on IL-1ß-provoked NF-κB as reflected by the expression of p-p65. NF-κB translocation inhibition with PS1154 reversed the effects of IL-1ß on IL-8 and sGAG. Collectively, miR-19b-3p attenuated OA by targeting GRK6-NF-κB pathway.


Assuntos
Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Quinases de Receptores Acoplados a Proteína G/metabolismo , Interleucina-1beta/metabolismo , MicroRNAs/metabolismo , Osteoartrite do Joelho/metabolismo , Idoso , Linhagem Celular , Condrócitos/patologia , Matriz Extracelular/patologia , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Transdução de Sinais
8.
Phys Chem Chem Phys ; 21(4): 1791-1796, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30624443

RESUMO

We performed first-principles calculations of the structural, electronic, and optical properties of heterostructures which consist of transition metal dichalcogenides MX2 (M = Mo, W; X = S) stacked with Mg(OH)2. All the heterostructures are formed by van der Waals forces. The MoS2/Mg(OH)2 and WS2/Mg(OH)2 vdW heterostructures were found to be semiconductors with indirect bandgaps and possess intrinsic type-II band alignment. In particular, a comparison of the band edge positions with the redox potential of water indicates that the heterostructures are potential photocatalysts for water splitting, enabling water reduction on the MX2 layer and water oxidation on the Mg(OH)2 layer. Moreover, the photogenerated charges will be effectively separated in the presence of a large built-in electric field across the interface. In addition, all of the MX2/Mg(OH)2 heterostructures show strong optical absorption in the visible and infrared regions, indicating their promise for application in photocatalytic water splitting.

9.
Eur Spine J ; 26(Suppl 1): 85-89, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27652680

RESUMO

PURPOSE: KBD is an endemic disease affecting the epiphyseal growth plate and articular cartilage of multiple joints, resulting in extremities' deformation and skeletal dysplasia. More attention has been paid to the visible deformed extremities instead of inconspicuous spinal condition. There is a lack of reports concerning the spinal radiological features, especially for the atlantoaxial joint. The aim of this paper is to report a case of a Kashin-Beck disease (KBD) patient diagnosed with atlantoaxial subluxation, concomitant with separated odontoid process fused to the enlarged anterior arch of the atlas. METHODS: We report the case of a 60-year-old woman with 54 years' history of KBD complaining of occipitocervical pain, decreasing motor strength and sensory function of both upper and lower extremities. Subsequent radiological examinations of lateral plain radiography, computed tomography scans and magnetic resonance imaging were performed to reveal these rare characteristics of atlantoaxial joint in this patient. Then, we review the associated articles to postulate whether this anomaly is accidental or linked in a KBD patient. RESULTS: She had an extremely rare variant with three aspects of characteristics: atlantoaxial subluxation concurrent with severe spinal canal stenosis and spinal cord compression, odontoid process separating from the body of axis, and the enlarged anterior arch of the atlas fusion with odontoid process. Comparing with the congenital anomaly of atlantoaxial joint, we postulated that this aetiology of anomaly might be linked to the acquired form attributed to the histopathology of KBD, rather than an accidental event. CONCLUSIONS: The anomaly of atlantoaxial joint might occur in KBD patients. Larger numbers of KBD candidates with earlier symptoms are recommended for radiological examinations of atlantoaxial joint, especially for the adolescents. Spinal surgeons are suggested to involve the research of the spinal anatomy and variation for the prevention and earlier therapy for KBD patients.


Assuntos
Articulação Atlantoaxial/diagnóstico por imagem , Atlas Cervical/diagnóstico por imagem , Luxações Articulares/diagnóstico por imagem , Doença de Kashin-Bek/diagnóstico por imagem , Processo Odontoide/diagnóstico por imagem , Compressão da Medula Espinal/diagnóstico por imagem , Estenose Espinal/diagnóstico por imagem , Atlas Cervical/anormalidades , Feminino , Humanos , Doença de Kashin-Bek/complicações , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Processo Odontoide/anormalidades , Radiografia , Compressão da Medula Espinal/etiologia , Estenose Espinal/complicações , Tomografia Computadorizada por Raios X
10.
Biochem Biophys Res Commun ; 478(1): 385-391, 2016 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-27416762

RESUMO

Kashin-Beck disease (KBD) is an endemic degenerative osteoarthropathy. The mycotoxin of T-2 toxin is extensively accepted as a major etiological contributor to KBD. However, its function and mechanism in KBD remains unclearly elucidated. Here, T-2 toxin treatment induced chondrocyte injury in a time- and dose-dependent manner by repressing cell viability and promoting cell necrosis and apoptosis. Importantly, T-2 suppressed the transcription of type II collagen and aggrecan, as well as the release of sulphated glycosaminoglycan (sGAG). Furthermore, exposure to T-2 enhanced the transcription of matrix metalloproteinases (MMPs), including MMP-1, -2, -3 and -9. In contrast to control groups, higher expression of insulin-like growth factor binding protein 2 (IGFBP2) was observed in chondrocytes from KBD patients. Interestingly, T-2 toxin caused a dramatical elevation of IGFBP2 expression in chondrocytes. Mechanism analysis corroborated that cessation of IGFBP2 expression alleviated T-2-induced damage to chondrocytes. Simultaneously, transfection with IGFBP2 siRNA also attenuated matrix synthesis and catabolism-related gene expressions of MMPs. Together, this study validated that T-2 toxin exposure might promote the progression of KBD by inducing chondrocyte injury, suppressing matrix synthesis and accelerating cellular catabolism through IGFBP2. Therefore, this research will elucidate a new insight about how T-2 toxin participate in the pathogenesis of KBD.


Assuntos
Apoptose/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Toxina T-2/toxicidade , Adulto , Apoptose/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Toxina T-2/administração & dosagem , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
11.
Clin Exp Pharmacol Physiol ; 42(11): 1207-19, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26218313

RESUMO

Epidural fibrosis might occur after lumbar discectomy and contributes to failed back syndrome. Transforming growth factor (TGF)-ß has been reported to influence multiple organ fibrosis, in which connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed 2 (CCN2) and CCN5 are involved. However, the effect of CCN2 and CCN5 on TGF-ß induced fibrosis has not yet been elucidated. This study reports that CCN2 and CCN5 play opposing roles in cell proliferation and transdifferentiation of human skin fibroblasts or rabbit epidural scar-derived fibroblasts exposed to TGF-ß. We observed that TGF-ß1 induced fibroblasts proliferation and differentiation in a dose-dependent manner (from 0 µg/L to 20 µg/L). Meanwhile, CCN2 expression is up-regulated while CCN5 expression is inhibited by TGF-ß1 exposure. Furthermore, it is demonstrated that CCN2 overexpression leads to promoted proliferation and elevated collagen and α-smooth muscle actin (α-SMA) expression, which are inhibited by CCN5 overexpression. Moreover, it is shown that the cysteine knot (CT) domain, present in CCN2 but absent in CCN5, plays an essential part in fibroblast proliferation and differentiation. Additionally, enhanced TGF-ß and CCN2 expression but decreased CCN5 expression is found in rabbit epidural scar-derived fibroblasts. Overall, the results show the opposing effects of CCN2 and CCN5 on fibroblast proliferation and transdifferentiation induced by TGF-ß.


Assuntos
Proteínas de Sinalização Intercelular CCN/metabolismo , Proliferação de Células/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Proteínas de Sinalização Intercelular CCN/genética , Células Cultivadas , Cicatriz/metabolismo , Cicatriz/patologia , Fator de Crescimento do Tecido Conjuntivo/química , Fator de Crescimento do Tecido Conjuntivo/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Espaço Epidural/metabolismo , Espaço Epidural/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Regulação da Expressão Gênica , Humanos , Masculino , Fenótipo , Estrutura Terciária de Proteína , Coelhos , Proteínas Repressoras/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
12.
Acta Biochim Biophys Sin (Shanghai) ; 46(11): 965-72, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25274331

RESUMO

Multiple myeloma (MM) is the most common cause of death from hematological malignancy worldwide, and recent studies have revealed that let-7b-5p can play an inhibitory role in tumorigenesis. However, the role of let-7b-5p in MM still remains unclear. The aim of this study was to elucidate the molecular mechanisms by which let-7b-5p acts as a tumor suppressor in MM. Here, quantitative real-time polymerase chain reaction results showed that the expression of let-7b-5p was remarkably reduced in MM tissues and MM cell lines (RPMI-8226 and U266 cells). Furthermore, over-expression of let-7b-5p significantly suppressed RPMI-8226 cell proliferation and induced S/G2 cell cycle arrest and apoptosis. Luciferase reporter assay results demonstrated that insulin-like growth factor receptor 1 (IGF1R) was negatively regulated by let-7b-5p at the post-transcriptional level. The mRNA and protein levels of IGF1R in RPMI-8226 cells were down-regulated by let-7b-5p. Furthermore, the cell phenotype altered by let-7b-5p inhibitor can be rescued by IGF1R silencing (si-IGF1R). Taken together, our results demonstrated that let-7b-5p functions as a tumor suppressor in MM, suggesting that let-7b-5p may be a potential therapeutic target for MM.


Assuntos
MicroRNAs/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Receptores de Somatomedina/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Humanos , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Receptor IGF Tipo 1 , Receptores de Somatomedina/antagonistas & inibidores , Receptores de Somatomedina/metabolismo
13.
Adv Mater ; 36(6): e2310023, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38029344

RESUMO

The exceptional lightweight, highly porous, and insulating properties of aerogel fibers make them ideal for thermal insulation. However, current aerogel fibers face limitations due to their low resistance to harsh environments and a lack of intelligent responses. Herein, a universal strategy for creating polymer aerogel fibers using crosslinked nanofiber building blocks is proposed. This approach combines controlled proton absorption gelation spinning with a heat-induced crosslinking process. As a proof-of-concept, Zylon aerogel fibers that exhibited robust thermal stability (up to 650 °C), high flame retardancy (limiting oxygen index of 54.2%), and extreme chemical resistance are designed and synthesized. These fibers possess high porosity (98.6%), high breaking strength (8.6 MPa), and low thermal conductivity (0.036 W m-1 K-1 ). These aerogel fibers can be knotted or woven into textiles, utilized in harsh environments (-196-400 °C), and demonstrate sensitive self-powered sensing capabilities. This method of developing aerogel fibers expands the applications of high-performance polymer fibers and holds great potential for future applications in wearable smart protective fabrics.

14.
Adv Mater ; : e2405533, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814659

RESUMO

Rechargeable Zn-air batteries (ZABs) are promising for energy storage and conversion. However, the high charging voltage and low energy efficiency hinder their commercialization. Herein, these challenges are addressed by employing precisely constructed multifunctional Fe-Co diatomic site catalysts (FeCo-DACs) and integrating iodide/iodate redox into ZABs to create Zinc-air/iodide hybrid batteries (ZAIHBs) with highly efficient multifunctional catalyst. The strong coupling between the 3d orbitals of Fe and Co weakens the excessively strong binding strength between active sites and intermediates, enhancing the catalytic activities for oxygen reduction/evolution reaction and iodide/iodate redox. Consequently, FeCo-DACs exhibit outstanding bifunctional oxygen catalytic activity with a small potential gap (ΔE = 0.66 V) and outstanding stability. Moreover, an outstanding catalytic performance toward iodide/iodate redox is obtained. Therefore, FeCo-DAC-based ZAIHBs exhibit high energy efficiency of up to 75% at 10 mA cm-2 and excellent cycling stability (72% after 500 h). This research offers critical insights into the rational design of DACs and paves the way for high-energy efficiency energy storage devices.

15.
Adv Mater ; 36(25): e2401234, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520380

RESUMO

Eutectic gallium-indium liquid metal (EGaIn-LM), with a considerable capacity and unique self-healing properties derived from its intrinsic liquid nature, gains tremendous attention for lithium-ion batteries (LIBs) anode. However, the fluidity of the LM can trigger continuous consumption of the electrolyte, and its liquid-solid transition during the lithiation/de-lithiation process may result in the rupture of the solid electrolyte interface (SEI). Herein, LM is employed as an initiator to in situ assemble the 3D hydrogel for dynamically encapsulating itself; the LM nanoparticles can be homogeneously confined within the hydrogel-derived carbon framework (HDC) after calcination. Such design effectively alleviates the volume expansion of LM and facilitates electron transportation, resulting in a superior rate capability and long-term cyclability. Further, the "dual-layer" SEI structure and its key components, including the robust LiF outer layer and corrosion-resistant and ionic conductive LiGaOx inner layer are revealed, confirming the involvement of LM in the formation of SEI, as well as the important role of carbon framework in reducing interfacial side reactions and SEI decomposition. This work provides a distinct perspective for the formation, structural evolution, and composition of SEI at the liquid/solid interface, and demonstrates an effective strategy to construct a reliable matrix for stabilizing the SEI.

16.
Nanoscale ; 16(4): 1751-1757, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38198211

RESUMO

Two-dimensional transition metal compounds (2D TMCs) have been widely reported in the fields of energy storage and conversion, especially in metal-ion storage. However, most of them are crystalline and lack active sites, and this brings about sluggish ion storage kinetics. In addition, TMCs are generally nonconductors or semiconductors, impeding fast electron transfer at high rates. Herein, we propose a facile one-step route to synthesize amorphous 2D TiO2 with a carbon coating (a-2D-TiO2@C) by simultaneous derivatization and exfoliation of a multilayered Ti3C2Tx MXene. The amorphous structure endows 2D TiO2 with abundant active sites for fast ion adsorption and diffusion, while the carbon coating can facilitate electron transport in an electrode. Owing to these intriguing structural and compositional synergies, a-2D-TiO2@C delivers good cycling stability with a long-term capacity retention of 86% after 2000 cycles at 1.0 A g-1 in K-ion storage. When paired with Prussian blue (KPB) cathodes, it exhibits a high full-cell capacity of 50.8 mA h g-1 at 100 mA g-1 after 140 cycles, which demonstrates its great potential in practical applications. This contribution exploits a new approach for the facile synthesis of a-2D-TMCs and their broad applications in energy storage and conversion.

17.
Small Methods ; : e2301476, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38183383

RESUMO

In the ever-evolving landscape of complex electromagnetic (EM) environments, the demand for EM-attenuating materials with multiple functionalities has grown. 1D metals, known for their high conductivity and ability to form networks that facilitate electron migration, stand out as promising candidates for EM attenuation. Presently, they find primary use in electromagnetic interference (EMI) shielding, but achieving a dual-purpose application for EMI shielding and microwave absorption (MA) remains a challenge. In this context, Sn whiskers derived from the Ti2 SnC MAX phase exhibit exceptional EMI shielding and MA properties. A minimum reflection loss of -44.82 dB is achievable at lower loading ratios, while higher loading ratios yield efficient EMI shielding effectiveness of 42.78 dB. These qualities result from a delicate balance between impedance matching and EM energy attenuation via adjustable conductive networks; and the enhanced interfacial polarization effect at the cylindrical heterogeneous interface between Sn and SnO2 , visually characterized through off-axis electron holography, also contributes to the impressive performance. Considering the compositional diversity of MAX phases and the scalable fabrication approach with environmental friendliness, this study provides a valuable pathway to multifunctional EM attenuating materials based on 1D metals.

18.
Research (Wash D C) ; 7: 0379, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779490

RESUMO

Cement-based materials are the foundation of modern buildings but suffer from intensive energy consumption. Utilizing cement-based materials for efficient energy storage is one of the most promising strategies for realizing zero-energy buildings. However, cement-based materials encounter challenges in achieving excellent electrochemical performance without compromising mechanical properties. Here, we introduce a biomimetic cement-based solid-state electrolyte (labeled as l-CPSSE) with artificially organized layered microstructures by proposing an in situ ice-templating strategy upon the cement hydration, in which the layered micropores are further filled with fast-ion-conducting hydrogels and serve as ion diffusion highways. With these merits, the obtained l-CPSSE not only presents marked specific bending and compressive strength (2.2 and 1.2 times that of traditional cement, respectively) but also exhibits excellent ionic conductivity (27.8 mS·cm-1), overwhelming most previously reported cement-based and hydrogel-based electrolytes. As a proof-of-concept demonstration, we assemble the l-CPSSE electrolytes with cement-based electrodes to achieve all-cement-based solid-state energy storage devices, delivering an outstanding full-cell specific capacity of 72.2 mF·cm-2. More importantly, a 5 × 5 cm2 sized building model is successfully fabricated and operated by connecting 4 l-CPSSE-based full cells in series, showcasing its great potential in self-energy-storage buildings. This work provides a general methodology for preparing revolutionary cement-based electrolytes and may pave the way for achieving zero-carbon buildings.

19.
Nat Commun ; 15(1): 1934, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431736

RESUMO

Ammonium ion batteries are promising for energy storage with the merits of low cost, inherent security, environmental friendliness, and excellent electrochemical properties. Unfortunately, the lack of anode materials restricts their development. Herein, we utilized density functional theory calculations to explore the V2CTx MXene as a promising anode with a low working potential. V2CTx MXene demonstrates pseudocapacitive behavior for ammonium ion storage, delivering a high specific capacity of 115.9 mAh g-1 at 1 A g-1 and excellent capacity retention of 100% after 5000 cycles at 5 A g-1. In-situ electrochemical quartz crystal microbalance measurement verifies a two-step electrochemical process of this unique pseudocapacitive storage behavior in the ammonium acetate electrolyte. Theoretical simulation reveals reversible electron transfer reactions with [NH4+(HAc)3]···O coordination bonds, resulting in a superior ammonium ion storage capacity. The generality of this acetate ion enhancement effect is also confirmed in the MoS2-based ammonium-ion battery system. These findings open a new door to realizing high capacity on ammonium ion storage through acetate ion enhancement, breaking the capacity limitations of both Faradaic and non-Faradaic energy storage.

20.
Adv Sci (Weinh) ; : e2401948, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769650

RESUMO

The integration of electrochromic devices and energy storage systems in wearable electronics is highly desirable yet challenging, because self-powered electrochromic devices often require an open system design for continuous replenishment of the strong oxidants to enable the coloring/bleaching processes. A self-powered electrochromic device has been developed with a close configuration by integrating a Zn/MnO2 ionic battery into the Prussian blue (PB)-based electrochromic system. Zn and MnO2 electrodes, as dual shared electrodes, the former one can reduce the PB electrode to the Prussian white (PW) electrode and serves as the anode in the battery; the latter electrode can oxidize the PW electrode to its initial state and acts as the cathode in the battery. The bleaching/coloring processes are driven by the gradient potential between Zn/PB and PW/MnO2 electrodes. The as-prepared Zn||PB||MnO2 system demonstrates superior electrochromic performance, including excellent optical contrast (80.6%), fast self-bleaching/coloring speed (2.0/3.2 s for bleaching/coloring), and long-term self-powered electrochromic cycles. An air-working Zn||PB||MnO2 device is also developed with a 70.3% optical contrast, fast switching speed (2.2/4.8 s for bleaching/coloring), and over 80 self-bleaching/coloring cycles. Furthermore, the closed nature enables the fabrication of various flexible electrochromic devices, exhibiting great potentials for the next-generation wearable electrochromic devices.

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