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1.
Nano Lett ; 23(4): 1564-1572, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36749889

RESUMO

Highly reversible Mg battery chemistry demands a suitable electrolyte formulation highly compatible with currently available electrodes. In general, conventional electrolytes form a passivation layer on the Mg anode, requiring the use of MgCl2 additives that lead to severe corrosion of cell components and low anodic stability. Herein, for the first time, we conducted a comparative study of a series of Mg halides as potential electrolyte additives in conventional magnesium bis(hexamethyldisilazide)-based electrolytes. A novel electrolyte formulation that includes MgBr2 showed unprecedented performance in magnesium plating/stripping, with an average Coulombic efficiency of 99.26% over 1000 cycles at 0.5 mA/cm2 and 0.5 mAh/cm2. Further analysis revealed the in situ formation of a robust Mg anode-electrolyte interface, which leads to dendrite-free Mg deposition and stable cycling performance in a Mg-Mo6S8 battery over 100 cycles. This study demonstrates the rational formulation of a novel MgBr2-based electrolyte with high anodic stability of 3.1 V for promising future applications.

2.
Nano Lett ; 23(23): 11233-11242, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37992235

RESUMO

Rechargeable magnesium batteries (RMBs) have been proposed as a promising alternative to currently commercialized lithium-ion batteries. However, Mg anode passivation in conventional electrolytes necessitates the use of highly corrosive Cl- ions in the electrolyte. Herein for the first time, we design a chloride-free electrolyte for RMBs with magnesium bis(hexamethyldisilazide) (Mg(HMDS)2) and magnesium triflate (Mg(OTf)2) as the main salts and tetrabutylammonium triflate (TBAOTf) as an additive. The TBAOTf additive improved the dissolution of Mg salts, consequently enhancing the charge-carrying species in the electrolyte. COMSOL studies further revealed desirable Mg growth in our modulated electrolyte, substantiated by homogeneous electric flux distribution across the electrolyte-electrode interface. Post-mortem chemical composition analysis uncovered a MgF2-rich solid electrolyte interphase (SEI) that facilitated exceptional Mg deposition/dissolution reversibility. Our study illustrates a highly promising strategy for synthesizing a corrosion-free and reversible Mg battery electrolyte with a widened anodic stability window of up to 4.43 V.

3.
Nano Lett ; 22(24): 10184-10191, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36475747

RESUMO

Two-dimensional metal dichalcogenides have demonstrated outstanding potential as cathodes for magnesium-ion batteries. However, the limited capacity, poor cycling stability, and severe electrode pulverization, resulting from lack of void space for expansion, impede their further development. In this work, we report for the first time, nickel sulfide (NiS2) hollow nanospheres assembled with nanoparticles for use as cathode materials in magnesium-ion batteries. Notably, the nanospheres were prepared by a one-step solvothermal process in the absence of an additive. The results show that regulating the synergistic effect between the rich anions and hollow structure positively affects its electrochemical performance. Crystallographic and microstructural characterizations reveal the reversible anionic redox of S2-/(S2)2-, consistent with density functional theory results. Consequently, the optimized cathode (8-NiS2 hollow nanospheres) could deliver a large capacity of 301 mA h g-1 after 100 cycles at 50 mA g-1, supporting the promising practical application of NiS2 hollow nanospheres in magnesium-ion batteries.

4.
Nano Lett ; 22(16): 6808-6815, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35947428

RESUMO

Metallic magnesium is a promising high-capacity anode material for energy storage technologies beyond lithium-ion batteries. However, most reported Mg metal anodes are only cyclable under shallow cycling (≤1 mAh cm-2) and thus poor Mg utilization (<3%) conditions, significantly compromising their energy-dense characteristic. Herein, composite Mg metal anodes with high capacity utilization of 75% are achieved by coating magnesiophilic gold nanoparticles on copper foils for the first time. Benefiting from homogeneous ionic flux and uniform deposition morphology, the Mg-plated Au-Cu electrode exhibits high average Coulombic efficiency of 99.16% over 170 h cycling at 75% Mg utilization. Moreover, the full cell based on Mg-plated Au-Cu anode and Mo6S8 cathode achieves superior capacity retention of 80% after 300 cycles at a low negative/positive ratio of 1.33. This work provides a simple yet effective general strategy to enhance Mg utilization and reversibility, which can be extended to other metal anodes as well.

5.
Nano Lett ; 22(22): 9138-9146, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36354212

RESUMO

Owing to its high volumetric capacity and natural abundance, magnesium (Mg) metal has attracted tremendous attention as an ideal anode material for rechargeable Mg batteries. Despite Mg deposition playing an integral role in determining the cycling lifespan, its exact behavior is not clearly understood yet. Herein, for the first time, we introduce a facile approach to build magnesiophilic In/MgIn sites in situ on a Mg metal surface using InCl3 electrolyte additive for rechargeable Mg batteries. These magnesiophilic sites can regulate Mg deposition behaviors by homogenizing the distributions of Mg-ion flux and electric field at the electrode-electrolyte interphase, allowing flat and compact Mg deposition to inhibit short-circuiting. The as-designed Mg metal batteries achieve a stable cycling lifespan of 340 h at 1.0 mA cm-2 and 1.0 mAh cm-2 using Celgard separators, while the full cell coupled with Mo6S8 cathode maintains a high capacity retention of 95.5% over 800 cycles at 1 C.

6.
J Am Chem Soc ; 143(31): 12145-12153, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324341

RESUMO

Methanol steam reforming (MSR) is a promising reaction that enables efficient production and safe transportation of hydrogen, but it requires a relatively high temperature to achieve high activity, leading to large energy consumption. Here, we report a plasmonic ZnCu alloy catalyst, consisting of plasmonic Cu nanoparticles with surface-deposited Zn atoms, for efficient solar-driven MSR without additional thermal energy input. Experimental results and theoretical calculations suggest that Zn atoms act not only as the catalytic sites for water reduction with lower activation energy but also as the charge transfer channel, pumping hot electrons into water molecules and subsequently resulting in the formation of electron-deficient Cu for methanol activation. These merits together with photothermal heating render the optimal ZnCu catalyst a high H2 production rate of 328 mmol gcatalyst-1 h-1 with a solar energy conversion efficiency of 1.2% under 7.9 Suns irradiation, far exceeding the reported conventional photocatalytic and thermocatalytic MSR. This work provides a potential strategy for efficient solar-driven H2 production and various other energy-demanding industrial reactions through designing alloy catalysts.

7.
J Am Chem Soc ; 142(45): 19259-19267, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33119292

RESUMO

Developing unique single atoms as active sites is vitally important to boosting the efficiency of photocatalytic CO2 reduction, but directly atomizing metal particles and simultaneously adjusting the configuration of individual atoms remain challenging. Herein, we demonstrate a facile strategy at a relatively low temperature (500 °C) to access the in situ metal atomization and coordination adjustment via the thermo-driven gaseous acid. Using this strategy, the pyrolytic gaseous acid (HCl) from NH4Cl could downsize the large metal particles into corresponding ions, which subsequently anchored onto the surface defects of a nitrogen-rich carbon (NC) matrix. Additionally, the low-temperature treatment-induced C═O motifs within the interlayer of NC could bond with the discrete Fe sites in a perpendicular direction and finally create stabilized Fe-N4O species with high valence status (Fe3+) on the shallow surface of the NC matrix. It was found that the Fe-N4O species can achieve a highly efficient CO2 conversion when accepting energetic electrons from both homogeneous and heterogeneous photocatalysts. The optimized sample achieves a maximum turnover number (TON) of 1494 within 1 h in CO generation with a high selectivity of 86.7% as well as excellent stability. Experimental and theoretical results unravel that high valence Fe sites in Fe-N4O species can promote the adsorption of CO2 and lower the formation barrier of key intermediate COOH* compared with the traditional Fe-N4 moiety with lower chemical valence. Our discovery provides new points of view in the construction of more efficient single-atom cocatalysts by considering the optimization of the atomic configuration for high-performance CO2 photoreduction.

8.
Angew Chem Int Ed Engl ; 59(44): 19570-19575, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-32652751

RESUMO

Two-dimensional (2D) mesoporous heterostructures combining ultrathin nanosheet morphology, periodic porous surface structures, and diverse hybrid compositions have become increasingly important for renewable energy storage and electronics. However, it remains a great challenge to develop a universal method to prepare 2D mesoporous heterostructures. Herein, we report a composite-micelle-directed interfacial assembly method to synthesize heterostructures of an ultrathin 2D material covered with mesoporous monolayers assembled on both sides. To demonstrate the concept, we first fabricated a new sandwichlike carbon@MXene@carbon mesoporous heterostructure through the self-assembly of exfoliated MXene nanosheets and block copolymer F127/melamine-formaldehyde resin composite micelles and subsequent thermal treatment. Finally, we demonstrate that the carbon@MXene@carbon mesoporous heterostructured nanosheets manifest remarkably enhanced electrochemical performance as a cathode material for lithium-sulfur batteries.

9.
Artigo em Inglês | MEDLINE | ID: mdl-39282747

RESUMO

The number of spent lithium iron phosphate (LiFePO4, LFP) batteries will increase sharply in the next few years, owing to their large market share and development potential. Therefore, recycling of spent LFP batteries is necessary and urgent from both resource utilization and environmental protection standpoints. In this review, the significance of pretreatment for LFP recycling is first underscored, and its technical challenges and recent advancements are presented. Following that, the current recycling methods for spent LFP cathodes are outlined in terms of the respective treating processes, advantages, and disadvantages. Additionally, the preparation methods of LFP cathode material are reviewed to guide the resynthesis of LFP that uses salts obtained from spent LFP, which are beneficial for closed-loop recycling of LFP batteries. Lastly, we explore the future development direction of spent LFP battery recycling, highlighting the importance of technological innovation to advance the sustainable growth of the LFP battery industry.

10.
Adv Mater ; 36(44): e2407398, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39275986

RESUMO

Ionogels are an emerging class of soft materials for flexible electronics, with high ionic conductivity, low volatility, and mechanical stretchability. Recyclable ionogels are recently developed to address the sustainability crisis of current electronics, through the introduction of non-covalent bonds. However, this strategy sacrifices mechanical robustness and chemical stability, severely diminishing the potential for practical application. Here, covalent adaptable networks (CANs) are incorporated into ionogels, where dynamic covalent crosslinks endow high strength (11.3 MPa tensile strength), stretchability (2396% elongation at break), elasticity (energy loss coefficient of 0.055 at 100% strain), and durability (5000 cycles of 150% strain). The reversible nature of CANs allows the ionogel to be closed-loop recyclable for up to ten times. Additionally, the ionogel is toughened by physical crosslinks between conducting ions and polymer networks, breaking the common dilemma in enhancing mechanical properties and electrical conductivity. The ionogel demonstrates robust strain sensing performance under harsh mechanical treatments and is applied for reconfigurable multimodal sensing based on its recyclability. This study provides insights into improving the mechanical and electrical properties of ionogels toward functionally reliable and environmentally sustainable bioelectronics.

11.
Nat Commun ; 15(1): 9364, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39478049

RESUMO

Magnesium (Mg) metal is a promising anode candidate for high-energy and cost-effective multivalent metal batteries, but suffers from severe surface passivation in conventional electrolytes, especially aqueous solutions. Here, we uncover that MgH2, in addition to the well-known MgO and Mg(OH)2, can be formed during the passivation of Mg by water. The formation mechanism and spatial distribution of MgH2, and its detrimental effect on interfacial dynamics and stability of Mg anode are revealed by comprehensive experimental and theoretical investigations. Furthermore, a graphite-based hydrophobic and Mg2+-permeable water-tolerant interphase is drawn using a pencil on the surface of Mg anodes, allowing them to cycle stably in symmetric (> 900 h) and full cells (> 500 cycles) even after contact with water. The mechanistic understanding of MgH2-involved Mg passivation and the design of pencil-drawn waterproof Mg anodes may inspire the further development of Mg metal batteries with high water resistance.

12.
World J Clin Cases ; 11(26): 6240-6245, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37731556

RESUMO

BACKGROUND: Endometriosis is a common benign gynecological disease that causes dysmenorrhea in women of childbearing age. Malignant tumors derived from endometriosis are rarely reported and are found in only 1% of all patients with endometriosis. Here, we report a well-differentiated squamous cell carcinoma (SCC) caused by squamous metaplasia of endometriosis that co-occurred in the uterus and ovaries. CASE SUMMARY: A 57-year-old postmenopausal woman had a 6-month history of irregular uterine bleeding. The uterus and adnexa were examined by computed tomography, and there were two solid cystic masses in the pelvis and right adnexa. Histological findings of surgical specimens showed well-differentiated SCC arising from squamous metaplasia of ectopic endometrial glands in the uterus and ovaries. The patient received chemotherapy after surgery and was followed up for 3 mo without metastasis. CONCLUSION: The continuity between ectopic endometrial glands and SCC supports that SCC originates from ectopic endometrial glands with metaplasia towards squamous epithelium.

13.
Mater Horiz ; 10(11): 5022-5031, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37644912

RESUMO

Green hydrogen produced via electrochemical water splitting is a suitable candidate to replace emission-intensive fuels. However, the successful widespread adoption of green hydrogen is contingent on the development of low-cost, earth-abundant catalysts. Herein, machine learning models built on experimental data were used to optimize the precursor ratios of hydroxide-based electrocatalysts, with the objective of improving the product's electrocatalytic performance for overall water splitting. The Neural Network-based models were found to be the most effective in predicting and minimizing the overpotentials of the catalysts, reaching a minimum in two iterations. The relatively mild reaction conditions of the synthesis procedure, coupled with its scalability demonstrated herein, renders the optimized catalyst relevant for industrial implementation in the future. The optimized catalyst, characterized to be a molybdate-intercalated CoFe LDH, demonstrated overpotentials of 266 and 272 mV at 10 mA cm-2 for oxygen and hydrogen evolution reactions respectively in alkaline electrolyte, alongside unwavering stability for overall water splitting over 50 h. Overall, our results reflect the efficacy and advantages of machine learning strategies to alleviate the time and labour-intensive nature of experimental optimizations, which can greatly accelerate electrocatalysts research.

14.
Nanomicro Lett ; 15(1): 21, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36580172

RESUMO

Rechargeable Al batteries (RAB) are promising candidates for safe and environmentally sustainable battery systems with low-cost investments. However, the currently used aluminum chloride-based electrolytes present a significant challenge to commercialization due to their corrosive nature. Here, we report for the first time, a novel electrolyte combination for RAB based on aluminum trifluoromethanesulfonate (Al(OTf)3) with tetrabutylammonium chloride (TBAC) additive in diglyme. The presence of a mere 0.1 M of TBAC in the Al(OTf)3 electrolyte generates the charge carrying electrochemical species, which forms the basis of reaction at the electrodes. TBAC reduces the charge transfer resistance and the surface activation energy at the anode surface and also augments the dissociation of Al(OTf)3 to generate the solid electrolyte interphase components. Our electrolyte's superiority directly translates into reduced anodic overpotential for cells that ran for 1300 cycles in Al plating/stripping tests, the longest cycling life reported to date. This unique combination of salt and additive is non-corrosive, exhibits a high flash point and is cheaper than traditionally reported RAB electrolyte combinations, which makes it commercially promising. Through this report, we address a major roadblock in the commercialization of RAB and inspire equivalent electrolyte fabrication approaches for other metal anode batteries.

15.
Small Methods ; 5(4): e2001018, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34927838

RESUMO

The sluggish transfer of electrons from a planar p-type Si (p-Si) semiconductor to a cocatalyst restricts the activity of photoelectrochemical (PEC) hydrogen evolution. To overcome such inefficiency, an elegant interphase of the semiconductor/cocatalyst is generally necessary. Hence, in this work, a NiS2 /NiS heterojunction (NNH) is prepared in situ and applied to a planar p-Si substrate as a cocatalyst to achieve progressive electron transfer. The NNH/Si photocathode exhibits an onset potential of +0.28 V versus reversible hydrogen electrode (VRHE ) and a photocurrent density of 18.9 mA·cm-2 at 0 VRHE , as well as a 0.9% half-cell solar-to-hydrogen efficiency, which is much superior compared with those of NiS2 /Si and NiS/Si photocathodes. The enhanced performance for NNH/Si is attributed to the contact between the sectional n-type semiconducting NNH and the planar p-Si semiconductor through a p-Si/n-NiS/n-NiS2 manner that functions as a local pn-junction to promote electron transfer. Thus, the photogenerated electron is transferred from p-Si to n-NiS within NNH as the progressive medium, followed by to Ni2+ and/or S2 2- of the defect-rich n-NiS2 phase as the key active sites. This systematic work may pave the way for planar Si-based PEC applications of heterogeneous metal sulfide cocatalysts through the progressive transfer of electrons.

16.
Int J Clin Exp Pathol ; 12(10): 3944-3948, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31933787

RESUMO

Epithelioid angiosarcoma is a rare soft-tissue sarcoma, which originates from endothelial cells. Herein, we report a case of an uncommon morphology of epithelioid angiosarcoma in the chest wall with diffuse hemorrhage and necrosis. The 52-years-old man suffered from severe chest pain, hemoptysis, and fever. Contrast-enhanced chest CT scans showed a large space-occupying lesion in the right chest cavity. A right thoracotomy was performed for definite diagnosis and surgical resection. Microscopically, the specimen demonstrated extensive hemorrhage and necrosis, while few visible tumor cells were noted. These cells were round to polygonal and even had an epithelioid appearance, with abundant eosinophilic cytoplasm. Vesicular nuclei and prominent nucleoli were observed. Immunohistochemistry indicated that these abnormal cells were positive for cytokeratin, vimentin, CD31, ERG, and FLI-1. They were negative for D2-40, CK5/6, calretinin, WT-1, CK7, TTF-1, napsin A, and CEA. Moreover, Ki-67 with MIB-1 was about 40%. On the whole, histology and immunohistochemistry supported the diagnosis of epithelioid angiosarcoma.

17.
Nanoscale ; 8(16): 8495-9, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27064740

RESUMO

A porous nanowire material consisting of graphene-amorphous FePO4 was investigated as an advanced cathode material for sodium ion batteries for large-scale applications. This hybrid cathode material showed excellent cycling performance and superior rate capability, which were attributed to the porous nanowire structure and the existence of graphene.

18.
World J Gastroenterol ; 9(3): 454-8, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12632496

RESUMO

AIM: To investigate the effects of tachyplesin on the cell cycle regulation in human hepatcarcinoma cells. METHODS: Effects of tachyplesin on the cell cycle in human hepatocarcinoma SMMC-7721 cells were assayed with flow cytometry. The protein levels of p53, p16, cyclin D1 and CDK4 were assayed by immunocytochemistry. The mRNA levels of p21(WAF1/CIP1) and c-myc genes were examined with in situ hybridization assay. RESULTS: After tachyplesin treatment, the cell cycle arrested at G0/G1 phase, the protein levels of mutant p53, cyclin D1 and CDK4 and the mRNA level of c-myc gene were decreased, whereas the levels of p16 protein and p21(WAF1/CIP1) mRNA increased. CONCLUSION: Tachyplesin might arrest the cell at G0/G1 phase by upregulating the levels of p16 protein and p21(WAF1/CIP1) mRNA and downregulating the levels of mutant p53, cyclin D1 and CDK4 proteins and c-myc mRNA, and induce the differentiation of human hepatocacinoma cells.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/farmacologia , Neoplasias Hepáticas/patologia , Peptídeos Cíclicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Células Tumorais Cultivadas
19.
World J Gastroenterol ; 6(5): 676-680, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11819673

RESUMO

AIM:To investigate the morphological and ultrastructural changes in the human gastric carcinoma cell line BGC-823 after being treated with tachyplesin.METHODS:Tachyplesin was isolated from acid extracts of Chinese horseshoe crab (Tachypleus tridentatus) hemocytes. BGC-823 cells and the cells treated with 2.0mg/L tachyplesin were examined respectively under light microscope, scanning and transmission electron microscope.RESULTS: BGC-823 cells had undergone the restorational alteration in morphology and ultrastructure after tachyplesin treatment. The changes were as follows: the shape of cells was unanimous, the volume enlarged and cells turned to be flat and spread, the nucleo-cytoplasmic ratio lessened and nuclear shape became rather regular, the number of nucleolus reduced and its volume lessened,heter-chromatin decreased while euchromatin increased in nucleus. In the cytoplasm, mitochondria grew in number with consistent structure relatively, Golgi complex turned to be typical and well-developed,rough endoplasmic reticulum increased and polyribosome decreased. The microvilli at cellular surface were rare and the filopodia reduced while lamellipodia increased at the cell edge.CONCLUSION:Tachyplesin could alter the malignant morphological and ultrastructural charact-eristics of human gastric carcinoma cells effectively and have a certain inducing differen-tiation effect on human gastric carcinoma cells.

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